This is possible in-game, at least somewhat, but it would have to be through some sort of existing magic on the server. Maybe take a look through a few of the magics on the Lord of the Craft wiki and see if you can find one that could possibly lead to your character being left as a "living ragdoll"? You should also clarify what you mean by that, and using existing magic to clarify it is even better.
The next step in making it really official would be to write a lore post about it. Talking to Lore Masters about making your idea work with the existing lore on the server will ensure that you don't get people saying "How come your character is like that? Is that breaking the rules?"
We all base our characters off existing people and ideas, to some extent. Our own characters are an extension of ourselves.
This depends on how far you intend on "basing" your character off an existing one. If you simply like the personality or mannerisms of a webcomic character and you want to emulate that in your own character, that's fine! The only thing that could possibly be going too far is making your character a one-for-one copy of that other character, especially if doing so would end up breaking server lore.
A good example I can think of is Sherlock Holmes. We had an organization on the server a long time ago called "Holmes", it was a detective organization. That's as far as the direct reference went, though. They didn't go around shouting, "I live on 221B Baker Street!" or "Elementary, dear Watson!" They were just emulating the style of Sherlock Holmes (detectives, magnifying glasses, pipes, etc.) in a way that could still be seen naturally on the server.
If that helps.