Rakshasa: Demon Rising

A feared gangster. A forgotten past. A contract with a monster from Hell. When Dojin Hong's girlfriend is kidnapped, he awakens the power of Rakshasa and is thrust into a hidden world of Contractors, Exorcists, and deadly supernatural creatures. To save her, he'll have to become the very monster he's been trying to leave behind.

(Source: WEBTOON)

Note: Includes one extra chapter.