>>280411534
Zaitsu is written as 座逸 in Japanese. Can't tell if there's a pun. I also wanted to check if the club by any chance referred to more specific genre of music, but it was フォークソング部 or "foukusongu-bu", so loan words from the English words "folk song club".

Sorry, not going for the untranslated background signs unless I am super curious.