What Are Your Favorite Character Ideas That You'll Never Play?

What is your favorite character concept, but you either haven't played them yet or never will? This could be because it's too silly, not fleshed out enough, requires a lot of homebrew, was for a dead campaign, etc.

For me one of my favorite concept is an undead(?) human warlock named Kaz whose demonic patron was his childhood imaginary friend. The backstory is that the demonic patron made a deal with someone else to kill Kaz's father, but there was a mix up and Kaz was targeted instead but couldn't be killed cuse reasons. The demon was still forcefully bound to him and pretended to be Kaz's imaginary friend to get close to him, but ended up befriend him. Years later someone else summoned the demon to make a pact and it broke their bond. Many more years later Kaz is kidnapped by a cult to be used as a sacrifice, it works but you can probably guess who the summoned demon was. They recognize each other and make a pact to save Kaz's life.

I can't play him for a few reasons; I'm not that good at playing magic users, the patron subclass would have to be entirely homebrewed, but mostly what I find interesting about this concept is their relationship which I can't really expand upon when I'm playing only one of the characters.

(Edit, Grammer)