noun
pornographic book; erotic book; hentai comic
Casual term for any printed pornographic material, including photo books and comic books (manga). Often used for explicit adult content.
彼はこっそりエロ本を買った。
He secretly bought a pornographic book.
部屋の隅にエロ本が積んであった。
There was a stack of erotic books in the corner of the room.