From age 11 to 13 I had a JO buddy. We would masturbate together several times every day. Not much to tell - - - we would just do a full hand grip, stroke really fast, and cum as quickly as possible. One time we did stroke each other - - only a few strokes - - wan't very good - - way too awkward. Now that i'm a lot older I have more and more fantasies about sharing with another guy - - and maybe lending a helping hand .
I'd love to engage in group whacking =P It'd be fun. Then again I'd just as much like to engage in group sex.
When I was in my late teens/early 20's (many years ago!) 3-4 of us used to jack off together. Fun! Ahhh the good old days!