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A boy who lacks confidence ignores the feelings of his childhood friend and accepts the confession of another girl, but he can't trust her feelings for him, so he uses information from a BDSM webpage to start training her into a sex slave, to test and see how obedient she'll be. The childhood friend, depressed and rejected, falls into the clutches of another boy who tricks and rapes her, then blackmails her to force her to go along with his own SM training plans. The two trainers now enter a competition: winner gets both slaves.