Oh, for sure. He thinks she's super cute, but he's a kid so he's embarrassed about it, which is why he's screaming that she's stupid all the time.
Puniru has only existed for 7 years so she's got no idea about anything other than that she likes Kotarou. That there are different kinds of "likes" is a concept that doesn't even exist for her.
It's a comedy manga, so my expectations are low, but it advertises itself as a "romcom" so maybe something happens eventually.