SW-341 My sister's friend is coming over to spend the night at our place, huh?! I can't stand it anymore with this zero-experience little brother being tempted by deliberate panty shots. "I'll let you do it after everyone falls asleep◆"

I can't believe my bland sister has such a sexy friend! The four sister friends who came to stay at our house deliberately flashed their panties on the stairs and in my room. They even dropped their towels in the bath, enjoying my reaction. I had my first experience while sneaking away from my sister's watchful eyes because of over-excitement. In the bathroom, quiet room, and living room, I was invited by the sister friends and secretly did it with all of them!