A BL queen graces us with a shoujo, lol. With a very relatable female lead. This is definitely a manga you shouldn't take too seriously.

A lot of reviews dropped it for fatphobia and

it is brought up in later volumes that these guys (except Mutsumi) only like her now that she's skinny and they need to reevaluate that. I also think it's important to note Serinuma herself doesn't care if she's fat or skinny though iirc she does start to notice how her appearance effects how men treat her. And she does end up with Mutsumi who from vol1 who had no preference on her appearance and just liked her personality.