Get yourself an Obama/Biden campaign pin and wear it to work. If the guy has poor personal hygiene and is always mumbling angrily to himself then he's definitely a conservative, and by wearing the pin you'll scare him away.
That sound like he is trying to up set you or get close to you, Just make sure he is not a mentally insane person.
no that's creepy.
Maybe, He wants to see if you will notice enough to cheer him up inside and outside(:-).
It's creepy. What does he smell like?