Kaoru Hana wa Rin to Saku (Manga) Wiki

Chidori High is a boys’ school that takes in the dregs of society with the lowest grades. Next door stands Kikyo Girls’ High, where the wealthy, high-class families send their precious daughters. Chidori second-year Rintaro, who has a fierce face but a gentle heart, is helping at his family’s patisserie when he meets a girl named Kaoruko. The two hit it off right away…but this blissful peace is quickly disturbed when Rintaro discovers that Kaoruko is actually a student at Kikyo. Worse, she doesn’t seem to realize what a huge problem this really is! Will these two be able to forge a path for themselves and sidestep the traps (metaphorical and literal) laid by their classmates?

Source: Kodansha