Narue no Sekai EP4 - My Younger Older Sister

Narue learns that her older sister, Kanaka Nanase, exists and is coming to visit with her caretaker, Bathyscaphe. When Kanaka goes to see Tadashi, she mistakes Narue as his wife, making her very angry and causing her to run away. When she checks back with Bathyscaphe in her escort ship, she realizes that Narue is her little sister who is dating Kazuto. After Bathyscaphe beams Kazuto up into the escort ship, Kanaka learns that Narue is technically older than her due to the Urashima effect. Bathyscaphe lands the escort ship, reconfiguring it into a house. After Narue tells Kazuto about her late mother, she visits Kanaka, who is upset about how much Tadashi has changed over the years. As Narue tries to restrain her, she accidentally shocks Narue with her stun gun, leaving Narue with a high fever. Kanaka, who believes that no one cares about her, is told by Kazuto that Narue was really looking forward to meeting her. The four wait all night long until Narue wakes up the next day, much to Kanaka's happiness.