Chain Man is an Other that Blake encounters during the "Execution" Arc, where he sought out souls to toss into Limbo and fill a quota. He was otherwise uninterested in the events.
A tall Other that wore what appeared to be a black skirt that trailed from a heavy belt that was about a foot tall. His chest was bare, and what looked to be disconnected bike or chainsaw chains trailed from his waist, arms, and neck, each chain ending in something wickedly sharp. Sawblades or caltrops of welded-together nails. He had long hair and an almost feminine cast to his features, owing to a lack of body fat, but he still looked eminently masculine with muscles and scarred skin.
Chain Man only seemed to be interested in finding more things to throw into the Machine and did not become instantly hostile despite the tolling of Molly's Bell. However he is indifferent to the suffering of those he collected.