Yoshikazu ended up going on a hot spring trip with relatives in place of his father, who couldn't make it due to work. Reuniting with his aunt, Yuna, who provocatively showed off her bewitching body, was far too stimulating for the young man... While secretly indulging in masturbation in the bath to calm his rising sexual desire, Yuna visited him. Overcome with lust at the sight of his rock-hard cock, she suddenly began to suck it... Urged to ejaculate time and again, Yoshikazu learned the pleasure of sex and fucked her like an animal. Yuna, who had been spending her days feeling unsatisfied with only her husband, also desperately sought him out...