i just love the mission where mogrul says drovas owed him money blah blah now hes untouchable. then he says try to kill me you'll get bounty blah blah. so i make sure its climatic, i take out my enhanced dwarven crossbow make sure i do a clean shot right in the head. however one thing comes to my head when i kill mogrul, wheres his bodyguard? i mean the dude vanishes after i kill mogrul.....

Probably realised he was out of a job now and decided to look for employment far away from the cause of that.

He probably has amazing sneak skills and hid from you while he snuck to the docks.

i guess but if i see him again i wonder what his dialogue will be?

On my game he stayed in town and his dialogue did not change, he still spoke as if Mogrul was still alive

There are actually 2 Morgrul's. One in DB and another as a member of the Dawnguard.

i know i was really surprised that their were two but i guess mogruls a popular orc name

I killed them both with just one explosive bolt in the Retching Netch so I've never had the bodyguard disappear.

They never go away. They will stay their for an eternity.

I meant I've killed them both so unlike the OP the bodyguard never disappears. If you are being facetious then excuse my comment.

Wait a minute...what the hell? I thought you were referring to the Cultists.

What in the world was I thinking?

Mogrul seems to spend most of his day giving Garyn Ienth a hard time, so I like to stuff Mogrul's body into Garyn's open chest. Fits in there quite snugly.

I think you had a little too much rum.