My Hero! (Tanaka Teko) summary:

Kae, who can’t seem to be as honest as she’d like to be, and Hiroto, self-conscious about his (lack of) height and childish appearance, are known for bickering all the time. Kae has kept her crush secret from Hiroto, but when he returns from summer vacation a tall and handsome flower boy… will she finally be honest about how she feels?