So this might be kind of an unusual fantasy, but I'm curious to hear people's thoughts on it. Some kind of evil or villainous female character is defeated and cornered, but instead of giving up, she decides to go out with a bang. Her body starts to bloat and expand and then soon she is laughing, holding her body and reveals that she is about to explode. Throughout the rest of the scenario, other characters have to either try to escape, try to stop her, or somehow move her out of there before she blows, and all the while she just keeps getting bigger and more unstable.