Soushitsu no Hibi ~Boukoku no Shounen Hen 2~

Takeru's life with his mother Koyuri and older sister Ayano was uneventful.
But, recently something was bugging him.
They were both wrapped up in a "foreign country fad", and he wasn't.
Specifically, he was clashing with K at school, a student from that country.

Other than that his life was fine. Takeru didn't really think much about it.

Then, his sister reached peak obsession, and found out Takeru had this "friend".
She invited K over to play at his house.