S1·E143 I Am the Most Unpleasant Person in the World

Shin-san accidentally gets involved with two low-class thieving morons, to Tatsugoro's horror. Tatsugoro finally manages to get rid of them, and one of them is promptly killed by evil ninjas for having seen something he should not have. Yoshimune learns they were raising a bunch of orphans in an awful shack with their scammed money, and decides he must avenge the dead criminal.