The Bugaria Theater is a building in the Ant Kingdom City where plays are held.
Most of the entertainment in the theater seems to come from Mothiva, although it is unlikely that she is the only actress/actor to hold plays.
There is one quest in this area, "Theater Help Wanted!", requested from Mothiva herself. The reward is 150 berries, after going through 3 fights. It is a repeatable reward. This is the only play seen in this area.