History#
Katsuki Bakugo grew up in the same neighborhood as Izuku Midoriya since they were young children. Izuku and Katsuki's other childhood friends gave him the nickname "Kacchan". Izuku and the other boys always looked up to Katsuki because of his energy, confidence, and natural-born talents (shown by his ability to juggle a football, read as well as making a stone skip seven times on water as a four year old; he was the type who could do anything he tried his hand at). Because of this praise, Katsuki developed a rather arrogant and self-inflated view of himself and would often pick on Izuku and gave him the nickname "Deku". Despite this, Izuku continued to follow him around.
Katsuki always admired All Might when he was young because the number one hero would always win against the odds. While watching a video of him at the electronics store, Katsuki tells his friends that All Might is the greatest hero because of his ability to achieve victory. When Katsuki was 6, he beat a few 9-year-olds in a fight, who bumped into him. With Izuku looking on, Katsuki says that the most amazing hero always wins no matter what.[1]
Once Katsuki developed his Quirk, his aggressive tendencies transformed into heinous bullying. He was constantly praised for his powerful Quirk and other talents. As a result of this, he developed a twisted superiority complex as a young child. Believing himself to be better than everyone else, Katsuki looked down on everyone, Izuku especially because he lacked a Quirk altogether.[2]
Despite this, Izuku still considered the two of them to be friends at the time, but things escalated when Izuku tried to help Katsuki after he fell off a small bridge into a stream. Izuku offered a helping hand, but Katsuki's pride caused him to take this an insult. He believed that Izuku made him appear as if he needed aid from someone who is much too beneath him.[2] However, deep down, Katsuki actually felt that Izuku was miles ahead of him due to his naturally selfless and heroic personality, something that he was unable to accept and resented Izuku for.[3][4] This would strain the relationship between the two for years to come, with Katsuki viciously bullying him, mocking Izuku for his Quirkless status and beating him up.[2]
During his second year in middle school. Katsuki, along with his two friends, came across Izuku at the Tatooin Shopping District. His friend with the long fingers then noticed the hero magazine that Izuku was reading and took it from him. Bakugo disparagingly threw the magazine back to Izuku from over his shoulder, but not without saying that a useless Quirkless person like him could only dream of being a hero. Just then, a villain suddenly appeared, using his Quirk to rob wallets and purses.
Despite Izuku suggesting that they should find a hero and his friends reminding him that public Quirk usage is against the law, Katsuki decided to chase down the villain in hopes of getting a recommendation to U.A. High School. However, before Katsuki could attack the villain with his Quirk, a powerful storm broke out, knocking him down and allowing the villain to escape. After the sky became sunny again, Katsuki wondered if that sudden storm was caused by the villain, and became more determined to capture him.
As Katsuki continued looking for the villain, he noticed Izuku doing the same on the ground and mocked his efforts. After analyzing the villain's Quirk more deeply, he realized that it was related to sand rather than clouds or smoke. After returning to the streets, Katsuki found the villain, having been reduced to a mud puddle by the unexpected storm. The villain blamed Katsuki for ruining his chances of getting away, but Katsuki intended to beat him nonetheless.
Right at that moment, the hero Airjet appeared and defeated the villain instead. Katsuki yelled at Airjet, but the hero just misinterpreted Katsuki's intentions for altruistic reasons and praised him. Katsuki then realized that Izuku must have deduced the villain's Quirk before him, infuriating him and causing him to generate further animosity towards Izuku.[5][6]