I love the genre too, tho a lot of them end up having more borderline h stuff. One I like is called Revenge classroom. There’s also one called hepatica/misumisou (which is fcking messed up btw. The art is also eh, and it ends really sadly.)
I recommend going to lists that have stuff about revenge probably. However, I also sometimes just search the revenge tag on bakaupdates. The only thing is that you have to be careful of ones that label it as “revenge” but it’s really just the MC borderline raping a character or something -.- like, I’ve read one like that and it was just godawful.
Sorry I can’t recommend more. I was really into this genre a few years back, but I stopped reading it after awhile cause there wasn’t as many good ones. I also forgot a lot about the ones I did read lol.
Though, another warning, most of them derail like midway or two thirds way through and the MC(and sometimes everyone else) gets a bad ending.
my favourite is http://www.mangago.zone/read-manga/brutal_satsujin_kansatsukan_no_kokuhaku/
you'll love it ε=ε=(ノ≧∇≦)ノ

I really can’t wait for this fcking asshole to get his face caved in. He’s absolutely horrible and I feel so bad for Shirakawa. I kind of wish the two twins would join in on this revenge ;;
I’m more for Shirakawa than azuma, since they both have history together and stuff. I kind of just want them to help and support each other, though there probably won’t be a good ending for the main character. I’ve read a ton of these series, and the mc usually never gets a happy ending, even after completing his revenge. However, I really hope there will be one, where he can be happy with his brother and they can hopefully heal from their past traumas after those monsters are fcking dealt with.