僕の彼女はデッカワイイ (Boku no Kanojo wa Dekkawaii)

Plot

For as long as he remembers, Komi has been shorter than his fellow classmates. He always felt inferior as a result, until he met Obinata - a girl who is head and shoulders above him.

Yes, Asumi Obinata is tall. She’s imposing. But she’s also Komi Amane’s girlfriend. And these two are the happiest kids in the world.

The super-popular oneshot has been expanded to a full series here!