So I read this manga a few years back and I couldn't remember it's title. But I've got clues, first I think the girl is in love with the guy but the guy looks ordinary and looks like Hidenori from DLHB and the manga doesn't seem to focus on romance rather on their lives i think. There's also one of the early chapters having a sports festival i think and I think that the girl and the guy played 3 legged race together. Also I'm not sure if it's 4 koma or not.