Mort
(Apprentice to Death)

Despite these drawbacks Mort was chosen by Death to be his apprentice, and during that time became considerably less undirected and considerably more serious.

But later...
...while he still has plenty of knees and elbows about his person, they seem to have migrated to their normal placves, and he no longer moves as though his joints were loosely fastened together with elastic bands. He used to look as if he knew nothing at all; now he looks as if he knows too much.

Andy Dick

Nicholas Brendon