At this point I don't remember where he comes in, but I do remember that Pluto and his house are very helpful along the way.
One thing to remember us to not get frustrated as the game advances. You are missing a bunch of event characters and more than likely always will. The trouble is that the interns at Gameloft who are for whatever reason in charge of the whole game constantly use these characters in each new event, hoping that new players will waste money on chests in the hope of winning them. Good luck. You're gonna need it.