It's a very poignant psychological drama with some horror touches. It's a very good read in 15 volumes, even though some parts of the story seem to linger a bit too much.

The story follows the kafkaesque journey to self-discovery of Nakoshi. Nakoshi, living in his car between a fancy hotel and a park populated by a group of homeless people is approached by a strange man, Itoh, with a lucrative proposition: agree to be subjected to a trepanation (drilling a hole in his skull) that could supposedly unlock psychic potential against as substantial amount of money. Thus begins the strange and disturbing "awakening" of Nakoshi.

I really recommend it it's a good read. It takes a deep dive in the characters' psyches and is a bit cerebral in its concepts but the artwork, beautiful and terrifying, really shines and makes the manga very visually compelling.

Warning : contains mature themes and some disturbing scenes/imagery.