Oh dear god. I got a similar sort of thing, only mine was a lot more... aggressive.

I started lucid dreaming naturally two years ago, and I still lucid dream about once every two months. I don't know how to control them, but I love it when it happens, although idk about you guys but I always feel absolutely exhausted and completely drained of emotion and imagination for days afterwards.

Anyway, I can always control my dreams. Except, twice, in my dream there was this man - he was always kind of unclear, though I noticed he wasn't particularly tall - more on the short side, actually - and he always seemed... angry. Like, very, very angry. With long dark hair. Both the times I encountered him, he pretty much smouldered in the corner while I tried to ignore him, and the minute I turned my full attention onto him to remove him from existance, he charged. As in, he just pelted towards me and started chasing me with this inhuman scream. I've never been able to change anything about him, though I've been able to change things on the way, like throwing doors open and trying to throw things in his path. I can't even make myself wake up; it's downright terrifying.

Of course, it's very different to your experience, but still. Thought I'd share.