The guy's imagination is not taken away. Waited for the girls to watch a horror movie and then came over and fucked each one in turn. When you wake up and see a mask, you involuntarily increase your state of fear. And this adds a twist to sex, more hormones are released, including adrenaline. it is possible that such tricks he and his sister and girlfriend will do regularly.
Marital sex just needs to be varied. If the couple won't do it together, then clearly they will still do it secretly each separately! I think this home variation is acceptable, in any case it is not as extraordinary as entertaining a large group of swingers. My wife and I once invited me to one of these, against her this clip is just sex puritanical family!
You want it now.