the act of having intercourse in a pool or lake and when finished drowning the partner for fun
Alex- what did u do last night?
Jack- water monstered this prostitute in wyoming.
Alex- YOUR A SICK MAN!
Christi- ughhh last night was so lame!
Christi- Jack thought it would be funny to water monster me but he decieded not too after i almost died.
Laura- what a jerk!
Christi- but its ok i seduced him into some sloppy seconds and water monstered that asshole myself