Recommended mangas?

[NotAniki]

Mangas where the MCs are vigilantes and have dark stories because of their past

 

[ryouhira]

@NotAniki first, what you mean by "vigilante"?

a member of a self-appointed group of citizens who undertake law enforcement in their community without legal authority, typically because the legal agencies are thought to be inadequate. - Google translate

So, you want an MC that punishing evil even through inhumane method, because of his dark past.
here some...

https://mangadex.org/title/25495/maou-no-ore-ga-dorei-elf-wo-yome-ni-shitanda-ga-dou-medereba-ii, The MC considered as Evil mage, but he done some good deeds like killing bandit or other evil mage.

"Goblin Slayer", only against Goblin tho.

well, that's for now, gonna tag myself to comeback later @Ryouhira

 

[Syanindita]

I believe Roppongi black cross fits with describstion

 

[NotAniki]

@ryouhira Yes. Thank you for the translation with the vigilante thing, cause english isn't my native language. And thanks for the recommendation too. Btw, yeah what I meant vigilante protagonists are like Juujika no Rokunin's mc and some other that I don't know. Maybe a backstory like Batman's and Daredevil's. Those kinds of Vigilantes