  We observed the 2012-2013 superoutburst of the newly identified transient SSS
J122221.7-311523 and found that this object showed successive two
superoutbursts. Superhumps grew in amplitude during the second superoutburst
and showed a characteristic pattern of period change reflecting the growth of
the superhump. Assuming that the periods of superhumps during the growing stage
[0.07721(1) d] and post-superoutburst stage [0.07673(3) d], represent the
dynamical precession rates at the radius of the 3:1 resonance and the radius
immediately after the superoutburst, respectively, we found that this object
has a very small mass ratio q=M2/M1 < 0.05. The possible orbital period from
quiescent data suggests q=0.045, one of the smallest among hydrogen-rich
cataclysmic variables. The long orbital period and low q make this object a
perfect candidate for a period bouncer. We suggest that the peculiar pattern of
double superoutburst is a result of a low q and may be characteristic to period
bouncers.
