Son raped his own mother

Lonely Seoulian Lee Kang works as an extorter of money from debtors. He cripples those who cannot repay the debt, simulating an accident, so that they can get insurance and pay off. But one day a woman appears on his doorstep, calling herself his mother, who abandoned him many years ago. Not believing her words, the guy rapes and cums inside her, but later the woman provides convincing evidence that she really is his own mother.
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