[Reducing Mosaic]YUJ-019 My coworker who looks plain but has a strong sex drive invites me to have sex every time we finish work. Anii Keika.

The senior at my part-time job, Kafun-san, took care of me after I got drunk. But I was so drunk that I couldn't walk properly, and worried Kafun-san let me stay over at her place. In the morning, I woke up with a throbbing headache from my hangover and saw Kafun-san sleeping in front of me, completely unguarded…! Soon after, when Kafun-san woke up, I couldn't help but kiss her. The usually plain and somewhat dull Kafun-san during work became so active once we had sex; I didn't know that about her.