lets say: The protagonist had a crush on an upperclassman, after longing for one year he decided to confess to her but got rejected. Sulking from heartbreak moment, his female classmate tries to cheer him on, and after one year worth of development and gaining much interest, our protagonist decided to have a meaningful relationship with her. But before he even got a chance, he got friend-zoned (or she already got a boyfriend). Spring comes around again when he got to know a freshman, and actually building up a meaningful relationship. But before the year ends, he got dumped.

Basically, something like that. One-time heart break doesn't count, multiple heart break from a single heroine is also out, heart break followed by heroine's suffering is unquestionably out, and of course each heroine should has a fair amount of time to shine. The close one I could get is Minamoto-kun Monogatari which based on Genji Monogatari.

So, any suggestion?