Akiteru has been planning his future as a video game developer for years, and he and his group have achieved some success with their latest release.
However, they are still high school students, and in an industry like that, they’ll need support at some point. Fortunately, his uncle is the head of one of the companies that could secure their entry into the big leagues.
Akiteru knows he needs to be professional and avoid asking his uncle for a favor. But sometimes it’s hard to be professional when Iroha, his best friend Ozuma’s younger sister, keeps sneaking into his apartment to play all sorts of pranks on him.
Ozuma tells him that Iroha must have feelings for him; after all, girls usually tease the boy they like, right?
Meanwhile, whenever Akiteru’s uncle calls, Iroha can’t help but drive him crazy.
At school, the story is quite different. Iroha is a model student, admired by everyone, and when she hints at having a relationship with Akiteru, everyone loses their minds.
He’s not surprised, but it starts to annoy him because Iroha tries to sweet-talk him with all sorts of compliments, only to end up making fun of him.
One evening, his uncle asks him to join him for dinner, saying they need to talk. Akiteru goes in full business mode, but receives a strange request.
Mashiro, his cousin, has decided to drop out of her private school and has transferred to the same school as Akiteru.
Her jealous father can’t stand the thought of anyone getting their hands on his daughter, so in exchange for supporting Akiteru’s video game development group, Akiteru must pretend to be in a romantic relationship with her.
(友達の妹が俺にだけウザい)
