Contains two stories.

[From ShoujoMagic]:

Story 1: 3D Material Suzushiro, a 19-year-old design student, was tired of living every day the same as the one before it, and that was why she agreed to give her virginity to Eiichi. He asked her in a bold and simple way; she replied simply, and there were no strings attached. Now, as Eiichi's eye wanders to Mizuno, a business student who's much cuter and more popular than Suzushiro, Suzushiro wants to know where she stands with Eiichi.

Story 2: Angel's Hallway