The protagonist wolf by the name of Jack lives in a wolven village.
It is a long tradition in the village that one has to join a festival
in order to be regarded as a full-fledged adult.

In the festival the ones to be tested challenge hunting game,
in which wolves chase after pigs to snatch bells from the pigs.

Three pig brothers Tet, Pit and Dat scheme to, driven by their
grudge against wolves, satisfy a certain kind of desire...

[From DLsite]