He can open any door or lock and steal anything his customers want as long as they pay the fee, so people call him "Key Jack."

A short story called Meiou Hades is included in v. 1: Amano Yuuichirou was hit by a car. When he next opened his eyes he found himself in a dark world full of monsters—and a young man with snow-white hair and jet-black eyes.

source: mangaupdates