IENE-433 When my older sister, who was dumped by her boyfriend, went on a hot spring trip instead, we ended up sharing a room in a mixed open-air bath!

An older sister brings her younger brother on a hot spring trip after her boyfriend suddenly cancels the trip, thinking it would be a waste. - I was supposed to go with my boyfriend, so naturally we had a mixed bath and shared a room. - I had an unexpected erection in my sister's big breasts that I wasn't always aware of! - As I was trying to hide it somehow, my sister approached me with her big breasts shaking. - I thought she would get angry if she found out, but my sister couldn't help but admire my erect dick...