He/she is a suspected or proven snitch. "Throw some water on him/her" refers to the snitch wearing a wire and the water ruining the device .

A way of warning that a person is a snitch
Throw some water on him/her is used as-
Throw some water on chad. He's been talking to the boss alot recently and I'm pretty sure he got tyler fired
by crzymnjohn October 7, 2020
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