Both KK and I love masturbation play, especially exhibition themed, group play. We've had many, many experiences; CFNM parties, Jack & Jill events, circle-jerks...
CFNM events are in a domain unto themselves, but don't always involve masturbation or sexual release. Some do, but not all.
Jack & Jill events used to be more common I think - these were basically soft swing parties, where the group masturbated together, watching, showing off. Most of these we attended "devolved" into harder, full swing, threesome or penetrating sex things. It was just too tempting, too much opportunity to waste.
In context, circle-jerks are most often gay/bi, all-male events. In my experience, three or more guys, masturbating together, usually to porn. Typical, these often go well beyond masturbation; mutual stroking, frotting, oral, maybe more. This is a very hot thing to engage in particularly in outdoor settings, in public, where you can be watched while pleasuring your cock and balls.
KK's done many "toy show" sorts of encounters, where she masturbates for a two or more men (including me), using her amazing toy collection - we watch, and jerk for her. These are some of my favorites; she loses her mind jilling off, forgetting there's even an audience, cumming, squirting, pissing, showing off her mind-bending orgasms.
KK also likes to have me masturbate for an audience - it was one part of my "punishment" for being "too greedy," by not sharing enough cum with her during the long holiday weekend's sex-fest. I was made to ejaculate into a shot glass, then drink it while KK, David, Andy and Paul watched.
