  We present a simple non-hermitian model to describe the phenomenon of
asymmetric tunneling between two energy-degenerate sites coupled by a
non-reciprocal interaction without dissipation. The system was described using
a biorthogonal family of energy eigenvectors, the dynamics of the system was
determined by the Schr\"odinger equation, and unitarity was effectively
restored by proper normalization of the state vectors. The results show that
the tunneling rates are indeed asymmetrical in this model, leading to an
equilibrium that displays unequal occupation of the degenerate systems even in
the absence of external interactions.
