|Fourth Period: Spinning Time|
|Romaji||Tsumugu no jikan|
|Manga Chapters||Chapter 88|
|Previous Episode||Itona Horibe's Time|
|Next Episode||Leader Time|
|Japanese||28 January 2016|
One week has passed since Itona joined Class 3-E. After Korosensei leaves for the day, Nagisa spots Itona building a high-tech RC tank. The boys marvel at the new student's talent considering how the tentacles had previously inhibited his intelligence (though he still has a sharp tongue) and are impressed at how silent the tank shoots and manoeuvres. Itona lets them in on Korosensei's critical weak spot - his heart directly underneath his crescent moon tie - a fact that Korosensei himself muses will be known eventually. Itona then takes the RC tank for a test run, driving it to the staff room until the boys see through its camera a few of the girls coming out. Most of the boys become completely distracted with the possibility of seeing up the girls' skirts and suggest various ways to improve the RC's camouflage and manoeuvrability. Only Nagisa and Isogai are weary of this considering how upset the class had been about the underwear thefts.
Early next morning, the boys test out the improved model again until it is destroyed by a provoked weasel. Despite the failure, Itona promises to keep on improving the design. Okajima's proclamation to see up all of the girls' skirts, however, is overheard by the girls, and an unfortunate timing by Ritsu to announce the completed development of a fish lens camera confirms the girls' suspicions. Okajima is left to fend for himself while Itona quietly slips away to skip class with Karma. Nagisa notes that Itona is quite sociable with everybody and knows that his talents can help assassinate Korosensei.
Later on, Kayano deciphers Itona's name meaning becoming a thread. Itona responds that other people in the class have weird names. She later spots Masayoshi Kimura's name, his full name meaning "Justice", a name he reacts to with chagrin. Because his parents were police officers, their fanatical belief in law and order led to naming their son Justice, and he cannot do anything about it. Kirara Hazama notes that she will never live up to her name because of her hysterical mother and living style, while Karma reveals to have inherited his parents' weird tastes to like his own name. Korosensei states only Irina and Karasuma do not call him by his designated name, though Irina reasons it is weird for adults to call him that. Yada comes up with the idea to call each other with code names they are given for the day, much like the assassins they encountered on the island. Each person writes down potential code names for everyone else which then will be drawn from a lottery box by Korosensei. Their teacher immediately bans everybody from using their real names for the day.
By the following PE class, however, most of the students were depressed with the names they were designated. Only Kimura was given his full name as his code name, with Korosensei reasoning that should Kimura be the one to kill him, the name Justice will resonate positively with the general public. In life though it is what people do that will define them rather than the names they were given at birth. When Korosensei suggests calling him "Prince of the Fateful Eternal Wind", the class riots and their teacher ends up being called "Stupid Pervert Chicken Octopus". Despite the students' general discomfort the class admit it was funny. Kayano, however, demands who gave her the name "Forever Flat", at which Muramatsu slips away.