I think this manga is cute. It shows childhood difficulties with gender-norms, sibling relationships, puberty and all that. Its refreshing too, definitely something different from all the other manga I've read. Somewhat realistic. For the romance side of things, there is one "relationship" that I think is really weird with one of the other side characters. But for the main characters, the age gap isn't that big of a problem with me but the ages are. It ain't too weird for someone young to admire someone older, but for someone older to like someone her age... it's a little weird. Luckily, I don't see many signsof him liking her in that way yet. (I'd like to think that so far he treats her like a sibling would).

I'm hoping for a time gap before the romance starts between them, at least till she's in late high-school. (Its pretty obvious who the main couple is right? There is a chance that it could change tho). As long as the romance isn't rushed I think this manga would do great in a slow-burn romance genre.