Shounen yo, Taishi toka Iroiro Idake manga at mangatensei.net,Chapter- 1.

When gorgeous transfer student Kazuma moves in to the ramshackle Akeboshi High Boys' Dorm #2, he immediately attracts the interest of resident airhead-with-a-heart-of-gold Masaji. Kazuma relentlessly rebuffs and abuses the other boy, but Masaji refuses to give up! After all, he just wants to be friends. Determined (for some reason?) to keep trying, Masaji chips away at Kazuma's abrasive aura, but could this sweet-and-sour feeling be what he thinks it is?! A super go-get-'em boy and a hot-and-cold beauty in a coming-of-age rom-com that includes a cast of colorful characters!