(Spoilers Extended) Bywater and Penrose are similar for a reason.

Bronn pushed a fall of hair from his eyes. "He's the best of them. But watch him, he falls into a rhythm, delivering the same strokes in the same order each time he attacks." He grinned. "That will be the death of him, the day he faces me."

Just like Ser Tallad, George often falls into a rhythm, delivering the same keystrokes and plot points. Not sure if this is by design or by habit, but it is present in his writing. As Bronn observes, if you watch closely and see the pattern, you can figure out what the next steps are going to be, even if George leaves it blank or--in another habit of his--throws a red herring at you.

One place where I believe George has fallen into a pattern is with Ser Jacelyn Bywater and Ser Cortnay Penrose. To my reading, George has written the same character twice applying only a minimal palette swap. Basically, first gen Ken and Ryu. Spotting the similarities between Bywater and Penrose is important because George presents us with a bit of mystery regarding the fate of Penrose. Penrose dies at some point shortly after Davos II of Clash without any witnesses as to how he died. I theorize we have everything we need to solve what happened to Penrose by recognizing Penrose and Bywater are following the same keystrokes and seeing through the red herring George is using to distract us.

Stubborn men

The first thing to note is Penrose and Bywater are each renown for being stubborn. This is their defining characteristic, and it permeates everything they do. It is one of the first things we are told about Bywater.

Lord Janos Slynt took a gulp of wine and sloshed it around in his mouth for a moment before swallowing. "Bywater. Well. Brave man, to be sure, yet . . . he's rigid, that one. A queer dog. The men don't like him. A cripple too, lost his hand at Pyke, that's what got him knighted. A poor trade, if you ask me, a hand for a ser." Tyrion II, Clash.

Shortly after our introduction to Penrose, we get this from Davos.

"A smuggler must be a fair judge of men," the king said. "What do you make of this Ser Cortnay Penrose?"

"A stubborn man," said Davos carefully. Davos II, Clash.

And Tyrion shares the view held by Davos.

"Link by link, it grows longer. We should thank the gods that Ser Cortnay Penrose is as stubborn as he is. Stannis will never march north with Storm's End untaken in his rear." Tyrion VIII, Clash.

These are not just one-off comments. Their stubborn nature influences everything they do.

Men honor

Penrose is also observed to have high standards for honor.

Lord Alester Florent cleared his throat. "Ser Cortnay, mind your tongue. His Grace means the boy no harm. The child is his own blood, and mine as well. My niece Delena was the mother, as all men know. If you will not trust to the king, trust to me. You know me for a man of honor—"

"I know you for a man of ambition," Ser Cortnay broke in. "A man who changes kings and gods the way I change my boots. As do these other turncloaks I see before me." Davos II, Clash.

In rejecting Ser Alester's self-assessment of having honor, Penrose tells us what honor is to him. It means you hold fast and do not change your position as it suits your needs. Essentially, honor means you hold the line even when it hurts. Which is a way of saying stubborn. Davos spots this.

Davos groped for some other answer. "Storm's End holds no knight who can match Ser Guyard or Lord Caron, or any of a hundred others sworn to your service. This single combat . . . could it be that Ser Cortnay seeks for a way to yield with honor? Even if it means his own life?" Id.

Penrose was left in charge of the castle and the boy Edric Storm. Yielding either of them is matter of honor for him. He is prepared to die rather than lose honor. Honor matters to Penrose just as it does to Bywater.

He laughed. "Ser Jacelyn thinks overmuch of himself and his honor, as I see it. You'll do better leaving that one where he is, my lor—Tyrion. Allar Deem's the man for you." Tyrion II, Clash.

By contrasting Bywater to Allar Deem, Janos tells Tyrion not only that Bywater is an honorable man but also Deem is not. And the Janos tells us why.

Tell me, why did you choose Deem for that unhappy task?"

"A good commander knows his men, Tyrion. Some are good for one job, some for another. Doing for a babe, and her still on the tit, that takes a certain sort. Not every man'd do it. Even if it was only some whore and her whelp." Id.

I take Janos saying Bywater is not like Deem to mean, Bywater it seems does not find it honorable to kill children and would have refused the task if Janos presented it. Bywater--a man of honor--will not kill children just like Penrose will not put Edric in harm's way. This brings us to the next way they share plot significance.

Each are tasked with protecting a king's son

Stannis wants Penrose the yield Storm's End and give up Edric Storm. Penrose will not give the boy up. This is non-negotiable for him.

"And the terms?" asked Ser Cortnay.

"Remain as before," said Stannis. "I will pardon you for your treason, as I have pardoned these lords you see behind me. The men of your garrison will be free to enter my service or to return unmolested to their homes. You may keep your weapons and as much property as a man can carry. I will require your horses and pack animals, however."

"And what of Edric Storm?"

"My brother's bastard must be surrendered to me."

"Then my answer is still no, my lord." Davos II, Clash.

The stubborn nature of Penrose shows itself again. Penrose refused a full pardon for himself and every man inside because he will not place Edric in the way of harm. He does not care that Stannis is King or is the rightful Lord of Storm's end. He is willing to put his life on the line, and in a point which should not be overlooked, the lives of the men inside.

The king pointed a finger at him. "I give you fair warning. If you force me to take my castle by storm, you may expect no mercy. I will hang you for traitors, every one of you." Id.

And also...

"Hungry for death, I call it. He throws my pardon in my face. Aye, and throws his life away in the bargain, and the lives of every man inside those walls. Single combat? Id.

The stubborn Penrose putting his men at risk will be important later in this analysis but for now, let's turn to Bywater.

Just a Penrose is tasked with protecting Edric, Bywater is given the task of keeping Tommen safe.

"Oh, I know. Tell Bywater to disregard what's in the letter and take his men north. He's to lay a trap along the Rosby road. Lord Gyles will depart for his castle in a day or two, with a dozen men-at-arms, some servants, and my nephew. Prince Tommen may be dressed as a page."

"You want the boy brought back, is that it?"

"No. I want him taken on to the castle." Removing the boy from the city was one of his sister's better notions, Tyrion had decided. At Rosby, Tommen would be safe from the mob, and keeping him apart from his brother also made things more difficult for Stannis; even if he took King's Landing and executed Joffrey, he'd still have a Lannister claimant to contend with. "Lord Gyles is too sickly to run and too craven to fight. He'll command his castellan to open the gates. Once inside the walls, Bywater is to expel the garrison and hold Tommen there safe. Ask him how he likes the sound of Lord Bywater."

"Lord Bronn would sound better. I could grab the boy for you just as well. I'll dandle him on my knee and sing him nursery songs if there's a lordship in it." Tyrion X, Clash.

"I need you here," said Tyrion. And I don't trust you with my nephew. Should any ill befall Joffrey, the Lannister claim to the Iron Throne would rest on Tommen's young shoulders. Ser Jacelyn's gold cloaks would defend the boy; Bronn's sellswords were more apt to sell him to his enemies. Tyrion X, Clash.

Bywater won't give up the safety of his charge...to anyone.

"Prince Tommen is hale and happy, my lord. He has adopted a fawn some of my men brought home from a hunt. He had one once before, he says, but Joffrey skinned her for a jerkin. He asks about his mother sometimes, and often begins letters to the Princess Myrcella, though he never seems to finish any. His brother, however, he does not seem to miss at all."

"You have made suitable arrangements for him, should the battle be lost?"

"My men have their instructions."

"Which are?"

"You commanded me to tell no one, my lord."

That made him smile. "I'm pleased you remember." Should King's Landing fall, he might well be taken alive. Better if he did not know where Joffrey's heir might be found. Tyrion XI, Clash.

Defiant in the face of royal commands

Bywater does not place his stubborn nature on hold for anyone.

"Yes. Her Grace bids me inform you that Ser Jacelyn Bywater defied a command issued in the king's own name."

Which means that Cersei has already ordered Bywater to release Pycelle, and been rebuffed. "I see." Tyrion VII, Clash.

Tyrion put Pycelle in the black cells and only Tyrion is giving Bywater the command to release Pycelle. Penrose is just as fearless.

"Enough!" Stannis said. "The Lord of Light willed that my brother die for his treason. Who did the deed matters not."

"Not to you, perhaps," said Ser Cortnay. "I have heard your proposal, Lord Stannis. Now here is mine." He pulled off his glove and flung it full in the king's face. "Single combat. Sword, lance, or any weapon you care to name. Or if you fear to hazard your magic sword and royal skin against an old man, name you a champion, and I shall do the same." He gave Guyard Morrigen and Bryce Caron a scathing look. "Either of these pups would do nicely, I should think."
[...]
"As the gods will it. Bring on your storm, my lord—and recall, if you do, the name of this castle." Ser Cortnay gave a pull on his reins and rode back toward the gate. Davos II, Clash.

This is good place to note another way the two are similar. Penrose is an old man, and Bywater lost a hand. George tells us something about this.

"Some might say a cripple and an old man are well matched. Jaime VI, Feast.

George is again demonstrating these are similar characters. Having established these character similarities and plot similarities, let's turn to the circumstances of their deaths to see if the similarities continue.

Similar deaths?

Penrose and Bywater face very similar situations before they die. Each in case they are in charge of holding a castle Stannis has under siege by sea and land. The men under Bywater's command are questionable.

Tyrion had no illusions where his own men were concerned. If the battle looks to be going sour they'll break, and they'll break bad, Jacelyn Bywater had warned him, so the only way to win was to make certain the battle stayed sweet, start to finish. Tyrion XIII, Clash.

The men on the walls of Kings Landing are not exactly super down for the cause. And we get a similar statement about men serving under Penrose.

"Then hear me. Ser Cortnay's lieutenant is cousin to the Fossoways. Lord Meadows, a green boy of twenty. Should some ill chance strike down Penrose, command of Storm's End would pass to this stripling, and his cousins believe he would accept my terms and yield up the castle."

"I remember another stripling who was given command of Storm's End. He could not have been much more than twenty."

"Lord Meadows is not as stonehead stubborn as I was." Davos II, Clash.

Penrose and Stannis are stubborn; Meadows is not. He is willing to accept the terms and thereby save his life and the lives of the men inside. The men of the Storm's End garrison face death because one stubborn man is the obstacle. Same thing played out with Bywater.

Pod's a good lad, but the knot in his tongue is the size of Casterly Rock, and I don't trust half of what he tells me. I sent him to bring Ser Jacelyn and he came back and told me he's dead."

"Him, and thousands more." Bronn sat.

"How?" Tyrion demanded, feeling that much sicker.

"During the battle. Your sister sent the Kettleblacks to fetch the king back to the Red Keep, the way I hear it. When the gold cloaks saw him leaving, half of them decided they'd leave with him. Ironhand put himself in their path and tried to order them back to the walls. They say Bywater was blistering them good and almost had 'em ready to turn when someone put an arrow through his neck. He didn't seem so fearsome then, so they dragged him off his horse and killed him." Tyrion I, Storm.

Bywater's stubborn nature got him killed. And we see this very same scenario play out in other mutinies.

• Jeor became the subject of a mutiny plot because he stubbornly wishes to fight 30k Wildlings with 300 men of the Watch. "Many of us," the Old Bear said. "Mayhaps even all of us. But as another Lord Commander said a thousand years ago, that is why they dress us in black. Remember your words, brothers. For we are the swords in the darkness, the watchers on the walls . . ." Chett, Storm.
• Dagon Codd is killed at Moat Cailin when he speaks against yielding to Ramsay. "It was the one-armed man who'd flung the axe. As he rose to his feet he had another in his hand. "Who else wants to die?" he asked the other drinkers. "Speak up, I'll see you do." Thin red streams were spreading out across the stone from the pool of blood where Dagon Codd's head had come to rest. "Me, I mean to live, and that don't mean staying here to rot." Reek II, Dance.
• Jon is killed by his men for being rigid on several choices which place the men of the Watch in danger.
• Robb refuses to yield his war with the crown despite having no hope of winning and is preparing to march him men into a deathtrap in an attempt to get back north.

With all this in place, George lays out a pretty clear formula for getting yourself killed in a mutiny. Be a stubborn man, facing an unwinnable situation, who rejects a reasonable alternative which would save the lives of the men under your command who do not share your view.

This describes exactly what Penrose faces in Davos II.

And given the many other ways he parallels Bywater; I think we can solve the mystery of how Penrose died by accepting it was a mutiny. And yes, how he died is a mystery. No character witnesses it. And we do not get an account from anyone inside the castle. Varys shares some whispers with us.

"Now tell me how Cortnay Penrose died."

"It is said that he threw himself from a tower."

"Threw himself? No, I will not believe that!"

"His guards saw no man enter his chambers, nor did they find any within afterward."

"Then the killer entered earlier and hid under the bed," Tyrion suggested, "or he climbed down from the roof on a rope. Perhaps the guards are lying. Who's to say they did not do the thing themselves?" Tyrion X, Clash.

Tyrion is asking the correct questions, aided slightly by his disdain for magical solutions.

Those who survived are spreading wild tales and swearing that the old gods of the north march with your brother."

"Then . . . there was no sorcery?"

Lannister snorted. "Sorcery is the sauce fools spoon over failure to hide the flavor of their own incompetence. My mutton-headed uncle had not even troubled to post sentries, it would seem. His host was raw—apprentice boys, miners, fieldhands, fisherfolk, the sweepings of Lannisport. The only mystery is how your brother reached him. Sansa III, Clash.

Tyrion rejects a magical answer for Stafford's fate, and he is correct to do so. Does it again here.

"A protective spell has been laid on the floors, hmmm, most powerful. Any fire in the cell below causes the floors to fall away, and the sand smothers the blaze at once."

"Not to mention the careless acolyte." By spell Tyrion imagined Hallyne meant clever trick. He thought he would like to inspect one of these false-ceilinged cells to see how it worked, but this was not the time. Perhaps when the war was won. Tyrion V, Clash.

And one more time.

"There's a place where Varys pushes, and it floats right up. I asked him how, and he said it was magic."

"Yes." Tyrion had to grin. "A counterweight spell." Tyrion II, Storm.

It would be fair to say "Tyrion did not see what happened below Storm's end. Book readers have." I admit it is difficult to reject Penrose dying by magic, when think you have seen magic take place below the castle. and this magic seems similar to what you saw in Renly's tent. Totally fine if you see it that way.

To my reading, whatever killed Renly and whatever is going on with Storm's End are not similar. Renly is killed by a force which opens doors, cuts steel, stabs flesh, gives off cold, and is telepathically linked to Stannis while he sleeps. None of this is present with Storm's End.

Penrose and Bywater are far more similar than what we know of Renly's tent and what we know of Storm's End. I just think the most similar path leads to the best answer.

So, what did take place below Storm's End if not a shadow assassin? It is pretty clear to me Davos saw a glamor rather than a real shadow assassin. Melisandre has a glimmer around her similar to Lightbringer, the thing Davos sees leaves no physical impact on the environment, then men outside Penrose's door did not see it go in, and it did not stab Penrose and leave the body like it did Renly. Beyond the visual, there is no reason to think the thing was ever really there.

Melisandre can use glamors and she see the future. Combining these two abilities, she can make it seem she is responsible for Penrose's death and thereby get the King's most trusted advisor to believe she has power while proving her worth to King. She has a practice of faking ability (Lightbringer) as well as taking credit for things she had nothing to do with (Orell's eagle and the deaths of Joffrey, Balon, and Robb). Given the complete lack of physical evidence that a shadow assassin killed Penrose, a mutiny really is a better answer than magic. Especially in light of the myriad other ways Penrose and Bywater parallel each other.

That is what I think. I am happy to hear your thoughts on the subject. Are Bywater and Penrose similar characters? Did Penrose face the same conditions other victims of mutiny faced? What evidence is there to support what Davos saw was real and went on to kill Penrose?

As always, polite disagreement and constructive criticism is welcome.

Tl:dr: George wrote Penrose and Bywater following the same basic template. They have similar habits, similar tasks, face similar obstacles, and I theorize they die by mutiny. Penrose was not the victim of a shadow assassin despite the show Melisandre put on. George repeatedly tells readers things believed to be magic often have a non-magical answer. Penrose's death is an example of something thought to be magical but most likely was not. The similarities between Penrose of Bywater are there to help us spot the deception which took place below Storm's End.