Second Virgin

One fateful morning, Hirofumi awakens to discover he has no memory of the previous two years. He has forgotten his classmates and everything he's learned at school. All he recalls is the car accident that caused his amnesia. When he finds a letter written to himself, he is shocked to discover that he has been romantically involved with the tragic and handsome Daigo! Can true love triumph over the loss of memory? And will Hirofumi be able to make Daigo smile again? (Source: Digital Manga Publishing)

A side story of Unmei ni Kiss and Sotsugyou, written and drawn by the same artist as Unmei ni Kiss.

Why do people always pursue what they can't have? Tsuda Yoshitaka can't get his mind off of his friend Takagishi Shigeru and his kind smile. However, Shigeru only cares about a woman that constantly jerks him around, neither promising nor giving anything in return. Frustrated, Yoshitaka decides that if he can't have everything, then he doesn't need Shigeru's smile anymore. (MAL)