Rin invites you over to practice a spell for the Holy Grail War, but something goes wrong. She loses control of her magic and gets stuck in her magic circle. Its power makes her feel horny, and she needs to cum in order to be released. She begs you to help her cum, in typical Tsundere style, saying between moans that she doesn't even care what you do, and definitely doesn't like you. So don't misunderstand, okay