Initial D dj - Osanai Koibito

From Futarikiri:

This appears to follow on from Saku Yamabuku to Shounen wa. Ryousuke and Takumi have been dating for one month now and Ryousuke invites Takumi for an overnight stay at a Hot Spring. The title translates to Very Young Lover. That's the issue Ryousuke has to deal with as Takumi struggles to find his feet in this relationship.

Pairing: Ryousuke x Takumi