The Sasaki family is as elite as it gets, and one of its members, Tetsunosuke, has joined the Shinsengumi.  He would have joined the Mimawarigumi, a police force with pedigree, but he is considered a troublemaker, which is why he was sent to the Shinsengumi.  Kondo assigns Tetsu to Hijikata as an assistant, so Hijikata is forced to endure the new recruit...
I know what you're trying 
to pull, frickin' Dankan!
¡Sé lo que intentas, maldito Dankan!
Eu sei bem o que fashion leader 
significa, desgraçados!