Mom invites daughter to join in the incestuous family fun.
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In so many ways, incest provides its own greatest alibi.
The act itself is so shocking, so forbidden, so fundamentally wrong; people can't seriously imagine that it's actually taking place. For most, incest can only exist as a form of abuse. A father sneaking into his daughter's bedroom late at night, to carry out wicked acts of molestation. An older brother or sister taking advantage of a younger sibling, wanting to satisfy their most base urges.
That people can believe. They might not imagine it could happen in their home or their family, but they know it could be happening somewhere.
But consensual incest? That's a different story. That seems a little more far fetched, a little more unlikely. Two closely related
