Cockserphobia originates from the word claustrophobia. Claustrophobia is the fear of being in a space that is too small. Cockserphobia is the fear of having more than one penis inside of you at one time.
Me: Hey Sarah want to have a threesome with two dudes this weekend?
The amount and variety of sexual experiences that any given man's cock (treated as a separate entity) should be entitled to, which may be hampered by it's 'owners' lack of sexual prowess, confidence, or unusually high standards.
"I don't care if he doesn't find her extremelyattractive... he should date her as he needs more cocksperience!"
"I'm nearly 40, and still a virgin... I need to ramp up my cocksperience!"