Hell is Dark with No Flowers vol 01 (manga)

Written by Yoru Michio
Art by Ruka Todo
Cover by Ruka Todo

Seiji Tohno sometimes sees the people around him as monsters. It’s a curse that has driven him to a life of despair…but all that changes one evening when he stumbles across a bewitchingly beautiful boy in a huge European mansion. The boy introduces himself as Shiroshi Saijou, and before he knows it, Seiji has agreed to become Shiroshi’s part-time assistant.

It turns out that Shiroshi’s “proxy service” is to consign yokai-possessed sinners to Hell, which will bring Seiji face-to-face with an unimaginable host of horrors!