Cock Block  

A cock block is a situation when somebody does or says things which prevents two other people, typically a male and a female that is, from talking, getting acquainted, hooking up, and ultimately having some sex for themselves. Cock blocks often happen in real-life social settings such as in bars and in nightclubs, but they can happen in the virtual world too, such as here on this site in chat rooms, or social networking sites, etc. The most common motive for the cock block is jealousy. Other motives for a cock block can play a factor too, such as a feeling of over-protectiveness on behalf of a friend, for example.

In your own experience, who would you say does the most cock blocks, and against whom do they do it?