Stiles and Molly were in Derek's loft talking to Cora. Derek was MIA, so they were trying to figure out what exactly was going on. Cora began telling a story. "They were here for two days, waiting, hiding. That's what we're taught to do when hunters find us... hide and heal."

Stiles took a moment to think. "Okay, so is two days standard, then, or are we thinking Derek's on, like, some extended getaway?"

Molly glanced at Stiles, then back to Cora. "Well hopefully he comes back."

Cora turned to Stiles. "Why do you care?"

"Why do I care?" Stiles repeated. "Let's see... because over the last few weeks, my best friend's tried to kill himself. His boss nearly got ritually sacrificed. A girl that I've known since I was three was ritually sacrificed. Boyd was killed by alphas. One of my best friends could have died fighting them. I... do you want me to keep going? 'Cause I can, all right? For, like, an hour."

Cora narrowed her eyes. "You think Derek can do anything about that?"

"Well, since he's the one everyone seems to be after, it's more like he should do something about it, yeah."

Molly tilted her head as she stared at Stiles. "Why are you the pessimistic one? I thought that was my job."

Cora rolled her eyes before saying, "There's something different about him now. He wasn't like this when we knew him."

"Then what was he like?"

"A lot like Scott," Peter answered, walking down the spiral staircase. "A lot like most teenagers... unbearably romantic, profoundly narcissistic, tolerable really only to other teenagers."

"Okay, what happened?"

"What changed him?" Stiles wondered.

Peter turned to him. "Well, the same thing that changes a lot of young men... A girl. A circumstance I'm quite certain you're familiar with, Mr. Stilinski."

Stiles subtly glanced at Molly and she said, "Okay, so a girl broke his heart. What happened?"

Peter reached the bottom of the stairs and placed his hands on the corners of the table. "Do you remember Derek before he was an Alpha had blue eyes? Do you know why some wolves have blue eyes?"

Stiles frowned. "I just always that it was, like, a genetic thing."

Molly shook her head. "Werewolves are different than humans. According to what I've read, their eye color changes are due to the death of someone. An innocent, right?"

Peter glanced at her and nodded. "That's right, Molly. If you want to know what changed Derek, you need to know what changed the color of his eyes."

He began telling them a story about a younger Derek and a girl named Paige Krasikeva.

Stiles frowned. "Okay, so if Derek was a sophomore back then, how old was he? How old were you? How old are you now?"

"Not as young as we could have been, but not as old as you might think."

Stiles rolled his eyes. "Okay, that was frustratingly vague. How old are you?"

"I'm 17," Cora replied.

"See, that's an answer. That's how we answer people."

"Well, 17 how you'd measure in years," Cora added.

Stiles shook his head. "All right, I'm just gonna drop it. What happened to Derek and the cello girl?"

Molly shot him a look. "Paige. Cello girl is Paige."

Peter stared at him. "What do you think happened? They were teenagers. One minute, it's "I hate you, don't talk to me." The next, it's frantic groping in any dark corner they could manage to find themselves alone for five minutes. Their favorite dark corner was an abandoned distillery outside of Beacon Hills."

Molly held a hand up in a stop motion and frowned. "Wait. How do you know this? You said they were alone."

Peter turned to her. "Back then, I wasn't just Derek's uncle. I was his best friend, his closest confidante. That's how I know how."

She jumped onto the table and crossed her legs on the table as she folded her hands.

Peter stood up and drew a spiral in the window condensation. "Our mark for vendetta."

Stiles took a sharp breath. "Man, you guys really take that revenge thing to, like, a whole new level, don't you?"

Cora shook her head. "It's not just revenge. Losing a member of your pack isn't like losing family. It's like you lose a limb."

"They wouldn't even let him see the body," Peter said.

Cora turned to her uncle and frowned. "I don't get it. What does this have to do with Derek?"

"Everything. It's never just a single moment. It's a confluence of events. Personally, I looked at Ennis' circumstances. I saw a profound loss. Derek saw something different. He saw opportunity."

"To do what?" Molly wondered.

"To always be with her," Peter replied.

Peter continued with his story. "The thing was, he had this constant fear. He was obsessing over it, thinking about it all night, always on his mind. I kept telling him not to do it. Everyday the more he thought about it, the more convinced he became. You know teenagers. I bet he even blames me. He's probably convinced the whole thing was my idea."

He told them about the emissaries and Cora informed, "They keep us connected to humanity. But they're a secret; even in the pack. Sometimes, only the Alpha knows who the emissary is. Derek and I had no idea about Deaton."

"Or his sister, Morrell," Peter added.

Molly raised an eyebrow as Stiles questioned, "She's an emissary too?"

Peter gave him a nod. "For the Alpha pack."

Stiles narrowed his eyes. "Our guidance counselor? Why the hell don't you people tell us any of this stuff, huh? Molly and I shared some really intimate details with her."

Cora turned to them. "And did she give you good advice?"

Molly shrugged. "Yeah, I guess."

Peter stared at her. "That's what they do. That's what Deaton used to do for Talia."

He went on to discuss the bite and Cora frowned at him. "Ennis? Why would he choose him?"

Peter shrugged. "Why not? Ennis needed a new member for his pack. Paige was young and strong. Doing a favor for Derek meant Ennis would be in good with Talia. Back then, everybody wanted to be in good with her."

Stiles asked, "He doesn't remember Ennis, does he?"

"If he does, he keeps it to himself."

"What happened to her? Did she turn?" Tabitha questioned.

"Almost," Peter answered. "He came at Ennis. A 15-year-old boy against a giant. There was no reason for him to fight. She'd already been bitten."

"So did she turn?" Cora wondered.

"She should have. Most of the time, the bite takes. Most of the time."

Stiles turned to Peter. "When you offered it to me, you said, ""If it doesn't kill you.""

"If."

Molly glanced at Stiles with a confused expression and he said, "The night you and Lydia got hurt at the Winter Formal."

"Oh. If is a big word."

"Yeah."

Peter continued. "I remember taking her body from his arms, to the woods, to a place where I knew that it would be found... another in a long line of Beacon Hills animal attacks."

"And what about Derek?" Cora asked.

Peter let out a sigh. "Taking an innocent life takes... like Tabitha said... Something from you as well, a bit of your soul... darkening it, dimming the once brilliant golden yellow to a cold, steel blue... like mine." He flicked his eyes to reveal steely blue eyes.

Molly stared at Peter a moment, realizing why Derek was the way he was.

Peter left, and Stiles gave a weird look to Cora. "What? What's this... what's this look on your face?"

"What look?" he asked.

"The kind of look that makes me want to punch you."

Stiles leaned back slightly. "Oh, my God. You are so Derek's sister. I forgot."

She nodded and frowned. "Well, what is with the look?"

Stiles let out a sigh. "I just don't believe him. All right, in Ms. Blake's class, we're reading Heart of Darkness, and it's in first person, right? Narrated by Marlow. The thing is that he's... he's an unreliable narrator. You know the details of it have changed, you know, just because of his perspective."

Cora gave him a slow nod. "Well, then we heard the story from Peter's perspective."

"And we need the other half," Molly stated.

Cora looked between the two of them. "So, what, are... Are you just gonna ask Derek about the girl he fell in love with and then killed?"

"If I have to... Yeah," Stiles said.

Molly shook her head. "No. That's a bad idea. After what happened with that girl seeing her dead boyfriend and what you asked her- Don't even think about it."

"Too late."