Basically, the characters are expected to do what Street Fighters do best - fight. More specifically, they will be invited to the Asakawa Trophy tournament. After a little legwork that will answer questions like "what is the Asakawa Trophy", the characters will be ready to enter the tournament.

The tournament should be fairly tough, though it should be stacked so that a PC wins it. Furthermore, at least one of the PCs should meet at least one of the NPCs that also have entered this tournament, in order to present the PCs with the Wolfmen that they'll encounter later on.

After preferably having won the tournament, the PCs should realize that they are being followed some time later. At a dramatically appropriate moment, the trophy gets stolen by the aforementioned Wolfmen. Tracking down the wolfmen, the characters enter their basement apartment in a bad part of the city, and finds it abandoned. One doorway is lined with parts of the trophy.

Stepping through the doorway, the PCs find themselves in another world. After encountering a sensei of some renown that can help them orient themselves in this strange, new world, it is time for some of that ol' ritual combat to get back to one's own world.

One ritual combat later, our heroes return to their own world, and have just realized that not only can people fly and throw fireballs - there's actually other worlds out there that they may sometimes reach - or meet denizes from there. Hopefully, they'll also be able to recover the trophy, in order to have it available for the next Asakawa Trophy tournament.