I fuck my stepsister's boyfriend while he fucked my stepsister

I have always suspected that my stepsister's boyfriend was bisexual, so I wasn't surprised when he got a boner while staring at my ass. Later that day, I lured my stepsister and her boyfriend to my bedroom and made my stepsister suck her boyfriend's cock while I fuck her pussy from behind. I also fucked my stepsister’s boyfriend's ass while he fucked my stepsister's pussy.