Bitching is when a character who was previously an alpha (or sometimes a beta) becomes an omega, either because there are too many alphas in the area, or because they’ve been regularly submitting to another alpha (sexually or non-sexually), or they’ve ingested or been exposed to enough of another alpha’s pheromones or bodily fluids that their biology starts to change around it. There’s a lot of variation and the mechanism that triggers the bitching can really be anything you want.

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