Magical Explorer, Vol. 2 (manga): Reborn as a Side Character in a Fantasy Dating — Sim Iris

Kousuke Takioto reincarnates as the unfortunate friend character in the world of an adult game. But just when he decides to use his game knowledge to become the strongest, he encounters a non-existent cohabitation route with the previously non romanceable beautiful mother and daughter pair! What’s more, even the main heroine is living with them too...?!