Mari Takada, a career woman, is raising children with her partner, Sayaka Kono. Balancing work and child-rearing, Mari believes the only connection she has with her son is through nursing and struggles to breast pump. But one day, she has to leave him with her mother, Mako (Meiko Kaji), due to a business trip, which triggers a change in Mari's stressed mind.

Emma is a British woman in Los Angeles trying to save money for a trip. While giving online lessons to international students, a Japanese man named Mamoru joins her class. Emma is shaken by a question from Mamoru. Feeling stuck in her life and unhappy with her ex-boyfriend, Emma finds new joy with Mamoru, but one day he suddenly tells her, "This is my last lesson."