A kev cry, is the act of leaving a conversation in a sad/angry mood which is used to make the people in the conversation feel bad/guilty about what they have done or said. The person doing a "kev cry" gains sympathy, at least attempting to to gain sympathy. not necessarily gaining it in the end.
A: You completely flirt with my friend
B leaves the conversation.
A: Why did he just leave?
C: He is away for a kev cry again.