Dr. Slump: Arale-chan - episode 6 - 19 May, 1981

Arale has told Senbei that a teacher is coming to their house. Once he hears this, he thinks Ms. Yamabuki is coming, so he has invented a barber machine to groom his hair to look nice. However, this barber machine is a failed robot. Arale and Gatchan meet a Bank Robber while playing outside. The Bank Robber tries to use them as hostages, but instead becomes fightened at them because Arale didn't get hurt when accidentally shooting herself with his gun and Gatchan nibbled a part of his gun when he tried to it as hostage. (Source: Wikipedia)