Here's another Dementor drawing. This one's got a creepy mask with a proboscis for super soul sucking. If sucking is your power, why not put it out there? Mosquitos don't hide their mouth way back inside a flat face, they put that sucker out front and center. 
It's got a little bit of ragged cape--not too much, and some severe pointy armor. Maybe not as creepy as yesterday's, but a little more functional.