Devy

"You don't look like you're from here... I guess you don't have much to lose, huh?"

- Talking to Hatsu.

Devy (데비) is a member of the Dooni tribe living as outcasts on the outskirts of the 49th Floor.

History
The Dooni tribe was hated by the Khukum tribe, which caused them to massacre all the of the Dooni, except Devy. Devy was kept alive and treated as a slave by the Khukum, most of the other tribes ignored his suffering, except the Fluffy Dwarves who were nice to him. Yeon Woon noticed his suffering and transformed his power into a hammer, which he gave to Devy to help against his oppressors.

Devy proceeded to kill all Khukum in sight, not letting any of them surrender even if they begged. Devy also started to chase away the other tribes, who did not help him in his plight. He wanted to live alone, only letting the Fluffy Dwarves who were nice to him stay. Yeon Woon asked for the hammer back, but Devy refused this request.

Tower of God: Part 3 - Deng Deng
Hatsu and Ship Leesoo travel to Devy in order to get the hammer back, since they need to wake Khun Aguero Agnis up. They initially does not get anywhere, but with some help from Little Yoon they manage to convince Devy to give them the hammer.