Suki ni Sasete Miseru kara! I'll Let You Like It!

Synopsis

Hiro Outa, a university student, is currently in a one-sided love with his childhood friend who lives next door, Shun Sakiyama. Hiro believes he's been slowly closing the distance between him and Shun, who was like a brother figure to him. When the time comes, he confesses, but he is rejected?! However, if there is even the slightest chance, he won't give up!! (Source: Kadokawa, translated)