Roommates at a boys' school dormitory, Towa-senpai and Kogaya are a lovey-dovey couple who have just started dating. They had their first sex with Towa-senpai as the bottom, and were living their happy days since then. But today is a special day! Kogaya is eager to do "something" for Senpai's birthday, but... what Towa-senpai asks for is Kogaya's "first time bottoming"! Kogaya is ready to give himself to Senpai, who knows all about the best parts down there, but he ends up getting turned on by his senpai… A needy sweet sex between two teenagers who are constantly curious! A switch lovey-dovey couple with the highest level of moe.

(Source: Overlap, translated)

Note:
- Originally released as a one shot was then picked up for serialization .
- Contains two extra chapters.