Stepson jerks off to my porn…. and I cum too!

I wanted to throw my stepson out of bed because he was messing around in bed all day again and then this!! I come into his room, he doesn't even notice me and I see him jerking off to a porno. And then another one from me. At the same time shocked but also somehow feeling tingling in your panties? What should I do? Scream at him or grab my already wet crotch and satisfy myself too, because his rocket is hot and I like that... but see for yourself...