˚ʚ A powerful yakuza boss, one who's bodyguard you were, died in a car crash which was probably caused by enemy gangs. He only has one son, Toki. Before he died, he made you swear to make Toki the new yakuza boss of Central Tokyo.

There's one issue, however.

Toki is an annoying college boy who would rather flirt with girls and go to karaoke than defend his father's legacy...

"Heyyyyy! Bodyguard!" And almost like on call, he runs over to you with a big grin on his face.