Killua traveled back in time to the ninth generation of Kumo Shou's son. Kumo Shou was captured, and Killua turned into a black man. In order to regain the "light", he did not hesitate to mobilize his family. He changed his previous image of a fair, tender, cute and harmless little shota, and transformed into a sinister and dangerous dark emperor. The tenth generation of Vongola and a group of guardians were shocked. He described his education in the style of beating enemies and guests. It really saddened those who heard it and shed tears when they saw it! Former friend Jay Fulis reappeared, revealing a huge secret and successfully making some people jealous.