Berty is the house in which Baba Yaga lives and runs her shop. Admittedly most houses do not have names, however this house is surprisingly unique in that it is non-stationary. The house actually walks around on a pair of chicken legs.
There is a glitch where when you enter the house, sometimes you will appear outside of the house along with Baba Yaga. You cannot move, and the only way out is to teleport. This glitch has not been fixed.