Erik

Erik (last name unknown) was an engineer working in the Bergman tunnels alongside with Robin.

Story
Erik used to work for the Bergmann Group in the Bergmann tunnels alongside with other tunnel maintenance workers until the company went bankrupt. After the bankruptcy, Erik was left to work alone in the tunnels until Robin showed up to help him. From the start Erik didn't trust Robin at all and he kept leaving angry notes to him all around the tunnels.

Throughout the years working with Robin in the Bergmann tunnels Erik begun to tolerate Robin even though Robin had a tendency to mess things up. At some point they even went for a mushroom trip together! Eventually Erik retired from his job at the Bergmann tunnels, leaving Robin to take care of the tunnels by himself. Evidently that didn't go very well.