"Are we really going to pick up Stiles?" Emily asked again, bouncing on the balls of her feet.

"Yes, we are," Peter assured her once again. Over her head, he shared an amused glance with Deborah who was trying to get her to put on her shoes and coat so that they could get going.

"I'm going to meet him before you," Emily told her mother as if she wasn't aware of that fact.

"I'm going to meet him soon. When Laura comes home," Deborah said, a smile playing on her lips. "But you have to tell me all about him later."

Emily nodded to that and for a second Peter wondered if this was a good idea. What kind of impression would the others get of Stiles from the report of a nine-year-old?

The older kids had gotten to know Stiles by now, they had picked him up for school again today, but they didn't have much to tell about him. Aside from the ride to and from school Stiles didn't hang out with them, most of the time he stuck to his friend Scott, but he still managed to keep an eye on the werewolves and on Kate as well. He gave Peter a report every day even if there wasn't much to tell. If Peter hadn't known that Kate was a hunter, he would have said that everything was normal at school.

The teenagers had accepted Stiles but like with everything else going on at school, they didn't share. Emily was different. She was a bubbling butterfly who would tell everybody willing to listen everything she knew about Stiles. And what she thought of him.

However, Stiles was waiting and Emily would just burst if she didn't see him soon, so once the kid was properly dressed with shoes and jacket, Peter grabbed her bag and ushered her out of the door.

Stiles was waiting for them where the path met the road, neither he nor Peter wanted Emily anywhere near the lake.

"Hey there," Stiles greeted them when he climbed into the car.

From the back seat, Emily was watching him with big eyes, at least for now speechless.

"You must be Emily." Stiles turned in his seat to face her. "Peter said that you're playing the guitar?"

"I'm learning," Emily clarified and Peter just waited for her to point out that they were on the way to her guitar lesson but instead she blurted out: "Do you really live in the lake? Like underwater?"

"Yes, I do." Stiles grinned at her.

"Are you a mermaid?" She leaned forward to have look at Stiles' legs. Which were just ordinary legs in tight jeans with red Converse at the end. However, Emily was part of a werewolf pack, she knew that just because somebody looked human that didn't mean that they were human.

"No, I'm not a mermaid." Stiles chuckled at that but he threw Peter a glance. "Is that what you told your pack about me?"

"Uncle Peter said that you live underwater," Emily answered for him. "That you live there with a lake monster. Does he have tentacles? Like Ursula?"

Well, that was quite an image. Peter was struggling to keep a straight face.

The way Stiles was choking on his own spit told him that Stiles' mind had gone in a different, not kid-friendly direction. Peter didn't want to know what kind of images the word tentacles had projected into Stiles' dirty mind but what made it even worse was the innocent look on Emily's face, eagerly waiting for details on Derek's appendixes.

"No," Stiles managed to choke out. "He doesn't have tentacles." He had to fight down the giggles at that word but he breathed through it. "He just looks like a man when he comes out of the lake."

Emily made a disappointed face.

Peter, on the other hand, filed away the piece of information Stiles had just dropped. If he looked like a man out of the lake, what did Derek look like when he was not out of the lake? He saved that question for later.

"But he can move through the pipes." Stiles tried to save the mood. "He can come out of every faucet."

"He can make himself that small?" Emily looked through the small ring she'd made with her thumb and index finger.

"He's basically water, he can go through the smallest pipes," Stiles told her which mostly answered Peter's question about Derek's form inside the lake. It did make sense.

"Are you water too?"

"No, I'm just boring old human." Stiles shook his head in clear amusement about her enthusiasm. "I just live with him."

"Because you have to stay with him." They had given Emily the cleaned-up version of what had happened to Stiles but she did know that Stiles had to stay with Derek.

"I do have to stay with him," Stiles confirmed. "But that's okay. I like Derek, he's my best friend. You have to stay with your parents, too, and that's not bad either, isn't it?"

She shook her head to that, easily accepting what he was telling her.

They arrived at their destination and Emily hurried to scramble out of the car to not be late for her lesson, Stiles forgotten for the moment.

"You're good with her," Peter said when they settled down in the waiting area. Usually, this was his time to hit the library but at the moment he did not feel comfortable with leaving Emily here alone. Maybe they could make a little detour on their way home.

"She's a curious little girl." Stiles stretched out his long legs. "And I like those open questions better than glances and whispers behind my back."

"I'll make sure to let the others now," Peter promised but his mind was on other things. What Stiles had said about Derek was still on his mind. Stiles had meant every word he'd said, Peter hadn't detected a lie.

"He is your best friend, isn't he?" When Stiles had called Derek his friend for the first time Peter hadn't believed him but back then he hadn't seen them together. Their relationship was intimate in a way that almost made him jealous.

"He is," Stiles agreed easily. "And before you ask, I don't mind staying with him, that hasn't been a lie."

"I know."

"You and your freakish werewolf senses." Stiles lowered his voice for that, they were alone in the waiting room but there were other people nearby.

"What is he?" Peter asked because that was still a mystery he hadn't been able to solve. "He's not a kelpie or a siren."

"That's the best you came up with?" Stiles huffed out a laugh. "I thought you have pages of notes, cross-references through dozens of books, and a list with your top ten guesses."

"I do have all that," Peter admitted, keeping a close eye on Stiles to catch every little reaction. "I narrowed it down to western European folklore but it feels like every little village has its own version of a water spirit. Without more information, it's impossible to tell exactly what he is." It was even possible that the myth about him had died centuries ago along with the people who had believed in it.

Stiles gave him a long look, clearly debating with himself. Peter tried to just sit there, slightly leaned back, open and relaxed, and waited for Stiles to decide if he trusted him enough.

Names held power. If Peter knew what exactly Derek was, he might be able to harm him.

"You know what's funny?" Stiles finally asked.

"Hm?" Peter gave him a curious eyebrow.

"The answer has been right in front of you the whole time." At least Stiles was enjoying this. Peter just waited for him to let him in on the joke. He didn't have to wait long. "He doesn't have a name."

"Did you name him Derek, then?" Peter wondered, not sure where this was heading.

"Kind of." Stiles nodded. "When I came to at the bottom of the lake, I was disoriented and freaked out. And I didn't speak German. Derek is me misunderstanding and mispronouncing what he introduced himself as." He paused, lost in fond memories for a moment but more for the dramatic effect, Peter guessed.

"And he introduced himself as …," Peter prompted when Stiles drew it out for too long.

"Der Nöck." Stiles grinned at him. "Get it? Der Nöck? Derek?"

Peter gave him an unimpressed look. That name, however, was familiar. It was one of about a hundred versions of that name, referring to similar water creatures all over Europe.

"I would have never been able to narrow it down to that," Peter admitted. "Thank you for telling me."

"Sure thing." Stiles was kicking his legs like a little boy, suddenly wary. "What are you going to do now?"

"I'm going to read up on him," Peter answered truthfully, there was no point denying it. He didn't see Derek as a threat, at least not at the moment, but it wouldn't hurt to know his weak spots.

"Figured that much."

"John has wolfsbane bullets," Peter reminded him. "It's only fair if I know how to defend my pack against a possible threat."

"Fair enough."

Peter's mind was swirling with what he knew about this particular creature and he couldn't wait to get home to find out more.

On their way home, they did stop at the library, though. Neither Peter nor Stiles had been here lately and they were done with the books Peter had gotten when Emily had been sick. They needed more.

Emily and Stiles got along well so Peter left them in the children's section to have a look around himself.

"Is that Stiles with your Emily?" Denise came over to him. Peter followed her gaze to where Stiles was animatedly discussing books with the little girl. She was hanging on his lips, looked like Stiles had a new fan.

"Heard what happened the other day," Denise said with pity in her voice. "Is it true that he and two of your kids were kidnapped?"

"Yes," Peter said clipped, he didn't want to feed her more to gossip about. "They managed to escape. The sheriff is doing everything he can to find those who did it." It was the official version which wasn't that far from the truth.

"How's he holding up?"

"Stiles? He's getting there," Peter said as vaguely as possible. He was thinking of the nightmare the other night but that was nothing Denise needed to know about.

"And the sheriff? He must have been worried out of his mind." She shook her head in sympathy. "Stiles is the only family he has left. After Claudia … he wouldn't cope well if something happened to Stiles."

She had hinted at that before, that John had been looking for comfort at the bottom of a bottle after his wife had died. But that was not the man Peter knew. Peter had seen John when Stiles had been missing. He had been worried and he had feared what the ordeal would do to Stiles mentally but he had known without a doubt that Stiles would survive and that Derek would get him out rather sooner than later. John had known that he would not lose Stiles which had helped him to stay focused.

If Peter was honest, he'd been the one more worried. Boyd and Erica could have died.

Peter changed the topic by asking Denise about books on European myths and legends. He doubted that he would find here more than he had in his library at home but it couldn't hurt to check. Looked like Stiles and Emily would be busy for a while anyway.

Peter did find a few interesting books and when he came back to the children's section, he found Stiles and Emily sitting on the floor with a stack of about ten books.

"Uncle Peter, look." Emily shoved one of the books into his face. "Stiles said he'll read it to me next time."

"Setting up dates already?" Peter raised an eyebrow. "Are you cheating on me?"

"I can read children's books to you if you're into that." Stiles winked at him.

Peter didn't even bother to answer that. Instead, he picked up the pile of books and went to check them out.

On their way out to the car, Stiles and Emily were still chatting about the books, which one Stiles would read to her first and with which one she would start on her own in the meantime. Why Peter was the one carrying the books he didn't know and he had to struggle to get the car keys out of his pocket without dropping the books.

Busy with the door, he didn't pay much attention to the car coming to a halt in the spot behind him.

"We need to talk," Chris Argent said.