Lover's Pledge(2005)

Koi wa Keiyaku no Atode

Kazuto loves being the life of the party...even when he can’t remember his wild night once the sun rises! But who’s this strange man curled up in his bed?! It turns out that the scrappy Kazuto has been purchased by the suave and successful Takasugi for an entire month. Everyone knows that you shouldn’t mix business with pleasure, but these two men will have a hard time playing by the rules if they let their bodies take control!

(Source: Juné)