Curious

My greatest fantasy is having sex with my boyfriend quietly in my room. After him eating me out and me sucking his cock, a knock at the door startles us. As we scramble to get dressed my roommate, who is a lesbian, asks to come in and watch. We let her in and continue having sex while she just sits there and watches, silently touching her self. After a while she gets up and starts doing some light touching. Feeling my nipples, teasing his balls, etc. She doesn't join in, not this time, but maybe some day soon.