An Argentine prostitute is charging that Don Omar spent two hot nights with her...and then skipped out on the $4,000 bill. On the TV show Al Rojo Vivo, she also said he's very dominant in bed, and likes S&M. Oh yeah, and that all this happened while he was already engaged to Jackie Guerrero. Of course, Don Omar denies knowing the prostitute and that nothing ever happened between them. Hmmm...ten cuidado, Jackie!