One morning, Junko, a mother whose husband is forcing her to have intense sex for the first time in a long time, can't stop her body from aching. She and her second son, Kenichi, try their best to have incestuous sex as usual, but only her son cums, and she doesn't cum. Unsatisfied, the mother goes to her eldest son, Junichiro, and has extreme incestuous sex with his older brother, who has a little more experience than his younger brother.