Even at the age of 70, Seiji's sexual desire still hasn't diminished, and he becomes sexually concerned about his granddaughter, Hana, who lives with him. Seiji, a former university professor, emphasizes that sex is a wonderful act, quoting Senka's Western literature, but Hana just looks down in embarrassment. One day, by chance, Seiji sees through Hana's secret sexual impulses and sets a trap for Hana...
