Girlfriend Insurance
The act of cheating in the beginning of a relationship, by any means defined as cheating, with a female, for the sole purpose of the "just in case she cheats on me" clause while hence in a relationship. Opposition definition "Boyfriend Insurance" aka "Slut" clause.
John got with Jane but heard she cheated on five other boyfriends, so John got girlfriend insurance and hooked up with Jane's sister Jill.