Sugar Glaze Darling

Keiichirou, who is actually the object of Reo's unrequited love, mistakes Reo for a girl and confesses to him. When Keiichirou admits to being bad at dealing with girls, Reo suggests that Keiichirou practice with him, while thinking of him as a girl... An impatient, fiery love story, as sweet as sugar, between a devilish, pampered boy and a straight-laced, super sweetheart.

(Source: Hakusensha, translated)