Forced weight gain is where a dominant will force the submissive to gain weight by taking control of their diet, forcing them to eat less healthily and in larger quantities.
This may be done over short periods of time, with the dominant literally forcing fatty foods into the mouth of the submissive, or it may be done over a longer time period, with the submissive being instructed to eat a certain amount per day and having to report back to the dominant in order to 'weigh in' and prove that they have gained weight.
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