MC's father is a serial killer called LL. the MC didn't know he has a split personality that kills people. also the name of the enemy gang is ISKALL which comes from I shall kill again -LL.
@mongs
Seems to be this one? 1st chapter mentions MC's father is a serial killer called LL
https://mangadex.org/title/33134/shin-ai-naru-boku-e-satsui-wo-komete
