In my room, where I'm a shut-in, I have a big TV and a lot of games to get me absorbed in playing games, but when my sister's friend found out about it, she asked me if she could let her play a game! She was super annoying, but she was cute, so I lent her a game for a little while, and when I saw her unprotected panty and breast flashes one after another, I couldn't help but stare at her and got a full erection! And when I thought it would be bad if she found out...