Yeah I've seen this happen with vials as well(they float midair, but if I go underneath them I can still pick them up), and once when I was soloing in the Graveyard, a Phantom followed me and appeared to descend to Moorcroft Mannor with me. It didn't appear there, though, and I'm not sure if that's even related with what you reported.
On a sepparate note, if I'm found dead in my room it's because I laughed myself to death looking at that guy. Seriously, this bug could be lifethreathening! :)