Sukusuku Otokonoko

Sukusuku Otokonoko summary:

From Intercross: Natsuyaki Hatsu is a first year student in high school. He's short, but he's in his growing period right now! As soon as he entered high school, he starts to get curious about a boy who's even more adorable than a girl, Fuyuno Aki. It turns out that Aki likes him and wants to have a relationship with him. Hatsu vows that he will reply to Aki as soon as he has become taller than Aki. And then there appears a tall and cool guy, Akimoto Kaname, who wants to make both Hatsu and Aki his. Aki doesn't like Kaname, but what about Hatsu...?!