Rikka's mother is preparing to remarry, and her new stepfather is a very kind and mature man. Seeing her mother so happy also makes Rikka feel happy for her. But witnessing the stepfather's skillful hip shaking abilities awakens a thirst for lust inside Rikka. Despite feeling very guilty towards her mother, she cannot stop herself. Pretending to be bitten by a mosquito, she asks her stepfather to apply medicine for her, and the bite is right in the middle of her buttocks, she has to pull down her panties to see it. Nevertheless, her stepfather remains composed and quickly leaves. Can he endure it once, but what about twice? Rikka often wears short skirts to reveal her full and perky buttocks with cute little T-back panties. She deliberately spills tea to bend down under the table, deliberately exposing her provocative swaying buttocks for her stepfather to gaze at carefully. And Rikka wins! That night, unable to resist anymore, the stepfather sneaks into Rikka's room. Of course, Rikka has been waiting for her stepfather all this time. Despite knowing this is wrong, Rikka's sexual desire surpasses the feeling of guilt towards her mother. Whenever her mother is away, they both passionately engage in each other, enjoying the pleasure and satisfaction that sex brings...