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'll repeat myself one last time!
¡Lo diré una última vez!
Vou me repetir novamente!