For a moment I ship the young brother with his cat friend but with that "He's nice, strong and cool" and that cute ass smile + blush... I don't know man, the author is giving harem vibes so hard (and Sakurai deserves that).
@RigobertoParedes a lot of people around them seem to assume that Sakurai and Fujisaki are together.
also, not to say this manga plays by these rules, but... she is the First Girl™