This was edging on really uncomfortable territory but... all things considered Reid already KNEW what that uncomfortable territory was. He didn't have much to hide, the man damn near hit the nail on the head. It wasn't complete and didn't have to be. What the other knew as bad enough and pretty much the meat of it. When it came to reasons it didn't really matter in the long run. Jethro was an evil man who'd warped Helix and molded him into a Hellhound to do his bidding.
In the end Helix betrayed him and so he punished Helix.
He shrugged, "Some sick fuck he hired to find me and teach me a lesson."
This much he'd worked out while he was held by the authorities a few days before waking up in Marina. That man... he'd told Helix things he knew, things Jethro told him.
"Jethro was vague on the details so ...he had his fun with it." He was back to being unable to look at Reid and sitting tensely. "But he was the one that set me up and incited a group of vigilantes." And, well... the rest is history really. He wasn't sure why he was telling him all of this but, he had to tell someone.
"Doesn't matter. He's dead." His tone shifted to something dark and smug. "Choked on his own dick." A glance at Reid, and the look in his eye was way too proud of what he'd done to him.
"Too bad his friends came back... I was too pissed to let them live either." And that's why he was here, because he'd lost control of himself and turned into that wild dog Jethro trained him to be. He'd never felt a blood-lust like that before and it felt GOOD to cut them open and hear them scream.