Matsuda Saves His Classmates by Switching Factions

*New writer, please be kind. *Amateur writing, terrible logic, mindless fun. *This is a fix-it story. Please point out any similar plot points, thank you. *The blurb may differ from the actual story, so read with caution. Thank you. *ABO story, but it's not very prominent. *HagiMatsu pairing; everyone else is friendship-only. A dazzling firework on the Ferris wheel brought Jinpei Matsuda's life to an end. He died in the line of duty at just 26. After his death, Jinpei Matsuda was bound to an artificially unintelligent program calling itself the [Black Side Experience System]. The System told Jinpei Matsuda how the five cherry blossoms ended up with 5-4=0, making his fists itch to give it a punch. But it claimed it could let him be reborn at the time he and his friends first met. Furthermore, the System said that as long as he survived until the organization was destroyed without anyone on the Black side suspecting him, the friend he saved wouldn't die in a ridiculous way by getting hit on the head by a flowerpot that fell from the sky. In other words, he could avoid his destined death. Matsuda looked at the screen, where his childhood friend was smoking without wearing a bomb suit, and agreed with a humorless smile. A month later, Matsuda clutched The Omega's Guide to Everyday Life and cursed the System for not telling him everything. Who could have guessed that being reborn would also mean transmigrating into a parallel universe?! Kenji Hagiwara sighed and once again asked online, troubled: What do you do when your childhood friend doesn't realize he's an omega? Theme: Live again, and leave no regrets