[UNCENSORED-LEAK] SONE-681 "She's too innocent to do what an older man tells her to do!?" I was attracted to my girlfriend's younger sister, so I secretly had sex with her. I'm such a terrible person.

I ended up teaching her younger sister, Ruka-chan. Even though she's a high school girl, she's still a child, innocent, and cute. She doesn't seem to have much knowledge about sex, and she flashes her panties and shows off her bra without a