Jimoto no Ijimekko-tachi ni Shikaeshi Shiyou to Shitara, Betsu no Tatakai ga Hajimatta. - Vol. 1 Ch. 7.1 - The Battle Where Nothing Is Visible Begins…

[Retro68]

While I don't care for any of them, if I had to choose, it'd be Shigure. They dug their own graves by bullying the crap out of him, something I personally cant stand seeing. That said, I don't particularly care for the mc either. He really does come across as an idiot.