1. Incest with a first cousin is illegal in most US states. This is where you two have the same grandparents.
2. Incest with a closer cousin has a much higher chance of producing a baby that has serious birth defects, which would then be unable to take care of itself, and become a drain on the state.
Beyond that, I don't judge what you do in your own bedroom.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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