BLK-627 I secretly love my sister.

When my parents remarried, I suddenly had a little sister! Moreover, since my room was my only child's room, I decided to share it. I'm worried... A hurtful word, "Dassa..." in a room full of otaku. But this sister is really a tsundere! I was a virgin, and I was too young to be able to make a broom as if to make fun of me, or to suck my cock when my parents weren't around! An older sister (Gal) and a younger brother (Otaku) with different clothes, personalities, and interests live together in an incest style!