  The gamma-ray emitting galaxy SBS 0846+513 has been classified as a
Narrow-Line Seyfert 1 from its spectroscopy, and on that basis it was thought
likely to have a small central black hole hosted in a spiral galaxy. But very
few of the gamma-ray Narrow-Line Seyfert 1s have high-resolution imaging of
their hosts, so it is unknown how those expectations hold up for the
gamma-emitting class. We have observed this galaxy in the J-band with the Large
Binocular Telescope's LUCI1 camera and the ARGOS adaptive optics system. We
estimate its black hole mass to lie between $7.70 \leq \log
\frac{\text{M}}{\text{M}_\odot} \leq 8.19$, using the correlation with bulge
luminosity, or $7.96 \leq \log \frac{\text{M}}{\text{M}_\odot} \leq 8.16$ using
the correlation with S\'{e}rsic index, putting its mass at the high end of the
Narrow Line Seyfert 1 range. These estimates are independent of the Broad Line
Region viewing geometry and avoid underestimates due to looking down the jet
axis. Its host shows evidence of a bulge + disc structure, both from
two-dimensional modeling and isophote shape, in keeping with the expectations.
Mergers and interactions appear to be common among the gamma-ray Narrow-Line
Seyfert 1s, and we see some circumstantial evidence for companion galaxies or
disturbed features in the host.
