Gossip Collateral

When two friends both know so many of each others' secrets that they both know neither one of them will tell, or the other one will tell in revenge. For example: Friend A knows X about friend B, and friend B knows Y about friend A. Therefore, if friend A reveals X, friend B may reveal Y, and vice versa. Thus, the security of their respective secrets is mutually guaranteed. Generally, the secrets in question are of equal or near-equal magnitude. For instance, cheating on a partner might be equivalent to a well-hidden drug habit or closet bulimia, whereas a crush would be a lower magnitude.

Becca told Rachel about her secret crush, and didn't have to worry about her telling, because she had Rachel's secret crush as gossip collateral.