This guy used an old-school bullying tactic with his girlfriend, and it did NOT go over well . . .

A 47-year-old idiot in Fort Pierce, Florida named Joseph Sireci was lying on the living room floor DRUNK when his girlfriend got home from work earlier this month.

Then he started arguing with her and being "rude," so she decided to go hang out at a friend's house.  But he tagged along and kept drinking while they were there.

Then while she was driving them back home, he reached over and gave her a WET WILLY.  And now he's facing battery charges for it.

When they got home, he kept being belligerent and also threw some stuff.  So she called the cops.

It's not clear if they're still dating, or if she dumped him.

(Miami Herald / TC Palm)

(Here's his mugshot.)