I'm a Chimera Ant, Not a Cursed Spirit Manipulator

Story blurb: Meruem was reborn as the younger brother of Geto, Gojo's future best friend. Seeing curses running all over the place, Meruem imitated his older brother and took a bite... From then on, the abilities he copied were all kinds of bizarre. Now that he was human, he no longer had to worry about balancing humans and Chimera Ants. His only regret was that he couldn't find Komugi. Meruem observed the new world and its people, but he was also gradually being changed by them. Little by little, he came to understand the apology given by the chairman of the Hunter Association in his previous life when he blew Meruem up with a nuclear bomb. But after finishing middle school, his older brother suddenly said he wasn't going to attend Ritsuri Sakura High School. He was going to a religious school instead. Representing their parents, Meruem felt Geto's forehead and asked, puzzled, "You don't have a fever, either." Geto was very firm about it. Meruem wanted to go along and have a look, but after Geto showed him a photo, he changed his mind. It was too remote, and Geto said he was going because of one person. Thinking Geto was going after something he wanted, Meruem believed him, until Geto came home one day and, without saying a word, went all out. Curses rampaged through the house. Their family, whom Meruem had thought were buried beneath the rubble, turned out to be safe and sound once the smoke cleared. Meruem casually cut down a curse and protected his panicked parents. Looking at the astonished Geto, Meruem frowned. "Geto, are you having an episode?" A gigantic vine shot into the sky, and Geto's curses began to fight back. Geto was stunned to discover that the younger brother he'd thought was an ordinary person wasn't ordinary at all. His plan to kill all of humanity had just hit a dead end. Meruem had just pinned down his older brother when a white-haired boy with blue eyes came running over, shouting, "Let go of Geto!" Meruem looked down at Geto. "Is that your Komugi?" Geto, still confused about how the weak weren't necessarily weak: ??? What Komugi? Meruem, who resembled Geto in some ways, had fallen into the original timeline, leaving everyone on high alert. Teacher Gojo: "Who are you?" A rough content warning: 1. This is a friendship story, with no Gojo x Geto or Geto x Gojo. 2. There are lots of author-added details, and the characters are very out of character. 3. The characters aren't very smart (because the author isn't very smart; this has nothing to do with the original characters). 4. The author is indecisive and didn't want Geto to suffer so much, so Geto's eventual change of heart ends up feeling very abrupt. Theme: Help others and find happiness