Because it's her son, the mother lets her guard down completely, wandering around in front of him with only a thin bath towel covering her naked body. Whenever that flimsy cloth slips open slightly, her son's desire for her erupts uncontrollably. The clear outline of his mother's figure begins to show through, making him wonder—could she actually want to be taken? At first hesitant, he gradually sees her not as a parent, but as an accessible target. Though he was still seen as a child, his lust had already grown too intense to suppress.