Things have escalated a little too far by this point for her masochism to just be cute or quirky (or moe to perhaps use a more appropriate term). I wonder how the author handles her from this point on. Given Yotsuha's cynical utilitarian stance on using the bullies by being open to them rather than directly confrontational, it's possible we might see a version of the "enemy becomes an ally" trope, but it's also possible that even if that happens the story -through Yotsuha's inner thoughts at the least- still condemns her rather than treating her as funny or cute.
I guess I'll judge once we actually see how it's handled. It's even possible that she just gets comeuppance and gets removed from the story, but I have to wonder why bother making up that motivation and her realisation here, if it's not going to be relevant to the story going forward.