Or, at least, that's how it looked to onlookers. In reality, Bloodhound was still alive!
But, after what Jin did to him, Bloodhound would have undoubtedly preferred a swift death.
In essence, Jin placed Bloodhound into an eternal sleep. This "sleep" was similar to a permanent coma; however, those affected by it were forced to perpetually relive what they believed to be the final moments of their life in a never-ending cycle. And, whenever they got remotely used to it, the method would change, digging into the thoughts of the inflicted and invoking their deepest fears before transforming them into an unmerciful nightmare.
But, it did not end there. The most terrifying part of the eternal sleep that made it so feared was that while it may only exist in the person's head, the pain they underwent felt completely authentic!
The majority of people who experienced this usually went insane within the first 24 hours.