Okay this is what I was thinking at first:
Cole, Jay, Kai, and Zane have the same class as Tamaki and Kyouya. Lloyd and Nya would come to Ouran later in the year. The villain is still undecided so suggestions are welcomed.
The girls of Ouran see the ninja as a mystery and Tamaki will try to pull the ninja into joining the Host club but they will refuse.
The rest is for me to know and you to find out. So are you interested? Are you going to help me?