  We report $^{77}$Se NMR data in the normal and superconducting states of a
single crystal of FeSe for several different field orientations. The Knight
shift is suppressed in the superconducting state for in-plane fields, but does
not vanish at zero temperature. For fields oriented out of the plane, little or
no reduction is observed below $T_c$. These results reflect spin-singlet
pairing emerging from a nematic state with large orbital susceptibility and
spin-orbit coupling. The spectra and spin-relaxation rate data reveal
electronic inhomogeneity that is enhanced in the superconducting state,
possibly arising from enhanced density of states in the vortex cores. Despite
the spin polarization of these states, there is no evidence for
antiferromagnetic fluctuations.
