Armin are a professionel fear hare, he are hired to scare people. He came to Sesamstrasse in episode 2421, where he scared Nils as he was trying to put together a new shelf. Rumpel ended up challenging Armin to a duel to find out who are better to scare other people. The competition ended up as a draw.

The rabbit puppet have been used in various roles on Sesamstrasse including Hasi Himmelglück and Knut Köffelström. He was originally used as Preston Rabbit on Sesame Street.