When Fujiwara, Natsu's former university teacher, gets injured, the couple decide to look after him. Natsu is a caring and considerate caregiver to Fujiwara, who has even helped her husband with his work. However, Fujiwara's desire for Natsu, who has become a married woman with firm skin and added sex appeal, grows. Then, while Fujiwara is being supported by Natsu as he climbs the stairs, he falls and buries his face in Natsu's crotch. Fujiwara's tongue wriggles like a living thing, and Natsu resists, but her body twitches as she feels it...