I had an idea a few months back.
I was planning to make a FUBAR supplement around it, but you could use easily apply the concept to just about any other traditional style roleplaying game.
You get a hero, this is a typical manga or anime hero. A young kid who gets into trouble, but who will become important to the fate of the world. The aim of the player characters is to teach the kid, to get them through the troubles of their youth in order to become the global hero they are destined to be...
Each of the player characters fulfils one of the archetypes of the setting.
In an anime-style setting, one player would be the friendly brute (who beats up bullies picking on the hero), another player takes on the role of the romantic mentor, another is the brainy one, then you get the comic relief (who might be the second best at a range of things), etc... there are dozens of these characters in anime, but they typically boil down to a specific combination from a small range of blatant stereotypes.
In a fantasy D&D setting, you might have the mage who instructs the hero in magic arts, the warrior who trains them in fighting arts, the thief who teaches them to keep their wits about them, the cleric who acts as a moral compass.
The key to this type of game is that the various mentor characters need to end up in situations where their specialties are challenged, and where they need to use their talents to overcome problems that might seem more tailored to one of the other characters (who is unavailable for one reason or another).
You could almost deconstruct this game concept using a game such as "My Life with Master". Instead of a master everyone slaves under, they are bound to this "golden child" by some prophecy or chain of events beyond their control. It'd be a very different take on the game premise, but just as interesting.