Otome Game no Heroine de Saikyou Survival - Ch. 28

[XNFEdayo]

she literally killed the entire killer guild.
if she's lawful, she'd go to the sheriff/law for it, wouldn't she?

maybe chaotic neutral.

If joking, good one.
If serious, yeah that's not what "lawful" means. It means that she has set rules/boundaries/convictions etc that she follows. This is why you can have "Lawful Evil" characters. "Chaotic" characters mean that in one way or another their actions are unpredictable.

Reason I say she's Lawful is: You help her, she helps you. You bare fangs at her, she'll unalive you. Despite being an assassin annnnnd kind of a murder hobo, she doesn't kill without reason. And once you get to know her, she's really easy to figure out.