I've a good friend on Lit who like me is married and extremely happy with sex in marriage. He and his woman play with dildos including a spunking one and they often share sucking one while they fuck. So, yeah, I'll be the real life other-guy-with-cock-ready for the two of them to play with!
Another scene which always has me revving when I see it in porn, is FFM with the girls lying one on the other at the edge of a high bed or such, breasts to breasts, and the guy, standing, is moving with ease from one puss to the other and back again, keeping things goin' for the girls with his fingers and occasionally his mouth too while he fucks. Yeah! I'd adore getting two gals orgasmic simultaneously like that!