  Although about 40% of the soft X-ray background emission in 0.4 to 1 keV
range has extragalactic origins and thus is totally blocked by the Galactic
absorption in midplane directions, it decreases at most by about 20 % in
midplane. Suzaku observation of the direction, (l, b) = (235, 0), showed an
OVII Kalpha emission intensity comparable with that of the MBM-12 on cloud
Suzaku observation, but revealed a narrow bump peaked at ~ 0.9 keV. The latter
component is partly filling the decrease of the extragalactic component in
midplane. The feature can be well represented by a thin thermal emission with a
temperature of about 0.8 keV. Because of the high pressure implied for
spatially extended hot gas, the emission is likely a sum of unresolved faint
sources. We consider a large fraction of the emission originates from faint dM
stars. We constructed a model spectrum for spatially unresolved dM stars that
consistently explains the observed spectrum and the surface brightness. The
model also suggests that the emission from dM stars decreases very rapidly with
increasing b, and thus that it cannot compensate entirely the decrease of the
extragalactic component at b ~ 2 - 10 deg.
