my first time having someone watch me fuck with my boyfriend

I had the most fantastic experience this afternoon. My best friend was staying with me for the weekend and had gone out to run some errands. I've been feeling particularly horny recently and decided to take advantage of her absence by having sex with my boyfriend. I'm on the bed, and his hands are caressing my pussy. I think I hear the front door open and close, but I'm not sure. His hands are caressing my clit, and I begin to moan, when my friend arrives into our room. We freeze in amazement as she walks into the room and sits in a chair. “Do you mind if I watch?” she asks. I smile at my lover as he leans in for a kiss and continues to stroke me. As he glides his palm over my clit, I start moaning again, and the thrill builds. Then my pal climbs onto the bed and places my head in her lap. “Make her cum,” she urges, looking my guy in the eyes. And she keeps encouraging him as I approach the climax. He's so aroused that he slides his dick into my pussy when I'm cumming. “Keep fucking her, make her feel so nice,” my friend says as she strokes my hair. My guy is fucking me while kissing my neck and caressing my clit. At one point, I crawl on top of him and begin riding him; he is moaning and his body is tightening as if he is about to charge. My friend encourages me and tells him to look at me. I continue until we are both ready to come, then I turn at my buddy and say, “tell me when,” and she keeps my gaze, touches my boyfriend's hair, and says, “go.” He and I begin cumming so hard that his cum fills my pussy with cum thrust after cum thrust. As we finish, he holds me and she lovingly brushes my hair before leaving the room with the words “until next time.”