Two years have passed, and Gintoki has shut down the Odd Jobs business and gone off to do something only he can do. Shinpachi has other ideas, though.
Long story short, it was 
because I had nothing to do.
.باختصار، لأنّني لم أملك شيئًا أفعله
Porque no tenía nada que hacer.
Dizendo de forma resumida,
é porque eu não tinha nada pra fazer.