In order to clean the pipes , Kiseru seperates the mouth piece and the front piece from the stem. He then inserts the mouth and the front piece into a type of fish tank where tiny fish swim into one end of the pieces and come out the other. These fish apparently live off tobacco residue and so they eat whatever tobacco is stuck to the walls of the pipe. In other words, they clean it perfectly. The two pieces are then taken out of the tank and fitted perfectly onto a new stem.
Kiseru pipes can be seen in the window of the mobile shop, some resembling Yuko and Watanuki's pipe, however, the Rabbit tells Watanuki that his pipe is much more beautiful than any other that he has seen and so it is assumed that the pipes that the rabbit sells are quite simple and so not have any extensive designs.
The rabbit and his shop are not part of Watanuki's dimension. The rabbit and Watanuki confirm this thought when Watanuki says that there are no fine kiseru sellers in his world and the rabbit tells him that in his world, there are a few good ones. This shows that the rabbit travels through dimension and worlds to complete his sales, though it is still unknown if the rabbit only travells to Watanuki's world, since Watanuki is his customer. or if the rabbit wanders around numerous worlds looking for clients.