That the sister is interested in her foster brother's opinion is commendable. And assessing her worthiness from a man's point of view he can. But asking him to jerk off in front of her is kind of weird. He's going to get her, isn't he? Only this slutty girl is not scared at all - that's exactly what she wants. He ended up flushing a whole puddle on her tummy! Drove it.
I've seen a lot of things, but I've never seen group sex on stage before. And the most amazing thing about it is that there are no bored faces in the audience! Everybody likes it! Well, direct participants are twice as pleasant: they suck your dick vigorously and the approving attention of the audience. The final chord, bukkake, is so organically blended into the atmosphere of the evening that you cannot help but wonder if it could have ended differently!
I'd get my ass in that one, too! After all, a Japanese couple records their sex for a reason, but for their friends. So they can cum on his wife too.