Bitch ni Natte, New Game! ~Game to Rendoushite Real Demo Henkasuru Ane no Sugata~

My sister is a self-indulgent, reclusive, and withdrawn person.
In an effort to rehabilitate her, I bought a "personality correction game."
While the game essentially involves defeating monsters, by linking a person's consciousness to an avatar, in-game elements affect that person's personality...
Apparently, this is a game. I immediately linked my sister's consciousness and began the game.
Selecting the tutorial to acquire skills,
I found myself performing blowjobs and having sex with a mob character.
After completing the act, I acquired the "Blowjob" and "Cowgirl" skills... but I wondered what would happen to my sister in real life.
Suddenly, my sister barged into my room.
"I-I don't really know what's going on, but... I-I can't stop feeling horny..."
Perhaps in heat, she forcibly pushed me down.
Convinced of the game's tremendous effectiveness, I resolved to continue the mission.
Little did I know, my sister would change more than I could have ever imagined...