  We report on optical and infrared photometric observations of a WZ Sge-type
dwarf nova, V455 And during a superoutburst in 2007. These observations were
performed with the KANATA (V, J, and K_s bands) and MITSuME (g', Rc, and Ic
bands) telescopes. Our 6-band simultaneous observations allowed us to
investigate the temporal variation of the temperature and the size of the
emitting region associated with the superoutburst and short-term modulations,
such as early and ordinary superhumps. A hot (>11000 K) accretion disk suddenly
disappeared when the superoutburst finished, while blackbody emission, probably
from the disk, still remained dominant in the optical region with a moderately
high temperature (~8000 K). This indicates that a substantial amount of gas was
stored in the disk even after the outburst. This remnant matter may be a sign
of an expected mass-reservoir which can trigger echo outbursts observed in
several WZ Sge stars. The color variation associated with superhumps indicates
that viscous heating in a superhump source stopped on the way to the superhump
maximum, and a subsequent expansion of a low-temperature region made the
maximum. The color variation of early superhumps was totally different from
that of superhumps: the object was bluest at the early superhump minimum. The
temperature of the early superhump light source was lower than that of an
underlying component, indicating that the early superhump light source was a
vertically expanded low-temperature region at the outermost part of the disk.
