Mutual masturbation is one way to have a safe sexual experience. Not only that, it's also kind of a race to see whose wank is the winningest.
We would never say anything bad about sex, but people definitely masturbate more than anything else. It seems like a shame to keep it all to yourself, right? And since the Masturbate-A-Thon is but once a year, people have to find their own ways to put all that, ahem, practice into good use.
· couple masturbation (xtube.com)