Step-Dad Demands Me to Fuck My Step-Sister Addison in Front of Him

I've always enjoyed fooling around with my step-sibling, Addison. Everything was going well until my step-father interrupted us, he just appeared in the room all of a sudden! He was secretly observing me and Addison the whole time, she was on the verge of giving me a blowjob. Now he insists that we engage in sexual intercourse right in front of him.
I am shocked that my step-father is just observing as I penetrate my step-sister's intimate area. Step-Dad instructs her to open her mouth and demands that I ejaculate right into her mouth for her to ingest it. I can not believe how twisted our step-father is, he is more deviant than me!.