I did this once drunk, but my ex wasn't responding to my texts. So late at night, I called her, but some guy picked up her phone. I became livid and said the most vile things to that dude. Tore him a new asshole. Told him all the things I already did with her to gross him out, and then hung up and cried. The next day she texts back "WTF did you say to my dad!?!" I blocked her number and moved on with my life. Don't often think about that one...