Usually my favourite episodes of Jani-ben involve Ohkura Tadayoshi throwing hissy fits or generally being extremely awkward.
eg: Yamada Hanako's amazing confession of love for Ohkura, and Kuwabataobara, with the most amazing love simulation story ever (and where i sorta found Maru amazingly manly for 3 seconds).
but this, really. i watched one same part three times over because it's really... really... funny. to me.
pull to about 6 minutes and Yasuda talks about the sounds of a violin, and he says it in a way that Maru catches onto immediately and Subaru turns it into a dramatic issue.