Koi mo Play mo Shoshinsha desu ga

Sui, who works part-time at an adult shop, realizes that one of the regular customers who always buys SM-themed porn videos is his university classmate, Toa.
Not wanting anyone to know about his secret desires, Toa pleads with teary eyes, “Please keep this a secret.”
On impulse, Sui offers, “Want me to be your S?” and the two decide to try out some beginner SM play together. When he makes the embarrassed Toa beg, touches, pinches, and teases him thoroughly, Toa ends up coming almost immediately...
Since that day, Sui hasn’t been able to get Toa out of his head and finds himself wanting to make him even happier...!?

(Source: Houbunsha, translated)

Note: Includes one extra chapter.