  We observed the 2018 November outburst of CS Ind and confirmed that it was a
genuine superoutburst with a very long [0.12471(1) d in average] superhump
period. The superoutburst was preceded by a long precursor, which was recorded
first time in SU UMa-type dwarf novae. We interpret that the combination of a
sufficient amount of mass in the disk before the ignition of the outburst and
the slow development of tidal instability near the borderline of the 3:1
resonance caused a cooling front to start before the full development of tidal
instability. This finding provides another support to the recent interpretation
of slow development of the tidal instability causing various phenomena similar
to WZ Sge-type dwarf novae in SU UMa-type dwarf novae with very long orbital
periods.
