  Stimulated by a recent work by Sumino, on the basis of a model in which
effective Yukawa coupling constants are described by vacuum expectation values
of a scalar $\Phi$ with $3\times 3$ components, a possible form of the scalar
potential $V(\Phi)$ which can well describe the observed charged lepton mass
spectrum is investigated without referring to a specific flavor symmetry model.
A general relation among eigenvalues of <\Phi> is derived without referring to
an explicit form of $V(\Phi)$.
