My stepsister wants to sleep with me and I end up fucking her hard until I cum in her

We are alone in our house and my stepsister is afraid of sleeping alone in her room so she calls me at my bedroom door to tell me if she can sleep with me and I tell her yes later I see her in her pajamas and I start to get horny because she sleeps without underwear and we start kissing until we both end up fucking I cum in her vagina at the same time that she cums too