It was cold comfort, but Pete was surprised at how easy it was to fall back on his training and view Kira's request as one more assignment he had to pull through. Certainly, he had lost his stomach for killing long before the flare made him persona non grata in British Intelligence, but that did not mean that he couldn't step into those shoes, become that guy who could kill anyone in cold blood if duty demanded it. Just doing what needs to be done, ennit? he asked himself quietly. He wasn't even sad about it. If he were to allow himself to feel sadness, or anything else for that matter, he would never be able to pull it off.
When all was said and done, Pete was pretty sure he would have asked for the same. It was the humane thing to do, even. He stepped forward and lifted Kira's chin with his hand, if she allowed it. When she called him as good as family, it was like being kicked in the chest, so he took refuge in humor.
"I bet you say that to all the boys, you daft minx," he cracked, all the while wiping furiously at the corner of his left eye. There was something in his eye, perhaps. Yes. That was it.
"Shh, luv. Don't apologize," he answered, shaking his head gently. "You are right, aren't you? The treatment failed. If this is your last request... I mean, if anyone's going to do it, it's going to be me, isn't it?" he said, and for a split second, his voice wavered. Pete set his jaw stubbornly and stamped down whatever had tried to jar loose just then. It wasn't easy, what with Kira's tearful eyes looking expectantly up at him. Pete hated this emotional stuff in that insensitive, hardwired male way. He wanted to punch things, to fix things, to make things better, but he couldn't. All he could do was do his friend a solid.
"In a way I'm honored you ask me," he said, and managed a little smirk. He finally lost the battle with himself and bent to a half crouch to draw Kira into a tight hug. "Just... say when." He thought about it for a moment and let go of her to gauge her reaction when he asked, "Do you wanna go peaceful like? In your sleep, perhaps? I'll stay with you all the way."