Omnia wo Suberumono

Misono Hinata and his childhood friend Ayakawa Suzuri had been living together for the past seven years. At long last, their life of sweet romance finally began now that Suzuri confessed her feelings. However, the sudden arrival of a girl named Satsuki, allegedly Hinata's cousin, resulted in a life of cohabitation for three. Despite having his hands full dealing with Satsuki's superpower, Hinata still continued to enjoy his romantic everyday life with Suzuri. Nevertheless, they were unfortunately caught up in the Misono head family's troubles--!?

(Source: Baka-Tsuki)