Becky, here's an idea with a backstory: You're in the bathroom, taking a shower. You ask your close friend, who's a guy, to sit in the bathroom with you and chit chat with you while you take a shower (the camera will be the guy's point of view). In the course of showering, you get horny and decide to show off a bit for this guy. At first you just tease him a bit, maybe show a little of your wet and slippery ass from behind the shower curtain. You work your way up to showing him your tits, all wet and soapy (you still do these little teases from behind the curtain, like giving him a quick flash of you). You wanna get him really hot and bothered, so, you show him your pussy, holding it open a little and posing it. Then you get even hornier, cause he's pulled out his cock and started masturbating while watching you. With the shower still pouring down on you, you open the shower curtain and lay down in the tub, watching him jerk off and you start masturbating. You finger yourself all while watching him jack himself off, ending with you both cumming at the same time. Maybe end it all with you with your mouth open, waiting for that off screen cum in your mouth.
Just a random idea based on what happened to me tonight.