There's lots of porn centred around cuckoldry where the guy gets off by watching (or being forced to watch) his girl having sex with other men, who invariably have bigger cocks than the guy. There's often an interracial element to it too.

Is there an equivalent genre that involves women getting off by watching their men have sex with other women? I think my partner would get jealous - and horny - if she watched me with a big-titted, big-assed black girl.

Cuckquean is the opposite of cuckold. There seems to be less porn surrounding it, unfortunately.

Yep...called a cuckqueen. It's less prevalent as part of the taboo of cuckold is the man being subservient and sometimes humiliated. Cuckold is the woman in power over her husband getting that good fucking he can't give her.

I'd love to see my wife fucked by a big cock.

Although I would prefer to see amateurs go at it, I think this is a good video http://xhamster.com/movies/3001323/cuckquean.html

I can only fantasize I wouldeat ray victoryssperm from Liz hurley