The follower from Morthal is one of the mob who accompany you to the vampire den but chicken out when you get there.
That plus when I asked him what he did he told me he hung around with the guards but they wouldn't let him join left me distinctly unimpressed.
I think my current character will hire him, take him somewhere there aren't any witnesses, then feed him to the Ebony Blade

Then it fits his character I suppose, he has a reputation for being a coward

. He's one of those followers who you brawl with and can have join you upon winning.
It'd be even more hilarious if the follower was a member of the Blades when this happened.
"Dragons?! You didn't tell me I'd have to fight dragons! I just signed up for the cool armor, I don't want to die!" *runs off*

Or, upon seeing a fellow Blade get snatched up in a dragons jaws, "They're eating her! And then they're going to eat me! Oh my Gawwwwwwwwwwds!"

(Let's see if anyone gets the reference)