Her husband is busy with work and rarely comes home. Because of that, they can't have sex, and Nami's libido is at its limit. One day, she witnesses her father-in-law, who lives with her, taking a nap with an erection. Nami, who is addicted to sucking, cannot resist seeing a penis that is bigger than her husband's and starts sucking it, crossing the line. Nami gradually goes crazy with pleasure and begs her father-in-law to let her satisfy his sexual needs...