He was a human hero, betrayed without mercy and handed over to the enemy in exchange for that laughable peace.
She was a vampire princess, and decided that if that was how things were, then she was done being human!
The useless shut-in hero turned into a piece of trash... a vampire princess, and set off on a path of stirring up trouble and seeking revenge.
But first, I need to stay far away from that sadistic trash queen!
After being put through brutal training by her mother, she was so furious she broke down inside, crying and making a scene. Poor thing.
At long last, she finally graduated and gained the ability to protect herself. But when she left the beginner's village, she discovered that there were bad women everywhere out here!
The noblewoman who had once been her brother-in-arms, sharing every hardship with her.
The golden dragon girl who meddled in everyone's business and claimed she was dispensing justice.
And...
"Ahem. We're both girls now, so it's perfectly normal for us to be close, right?"
"Right, totally normal. Bro, you smell so good."
"Ah! What are you doing? Don't come any closer! Don't come any closer!"
The idiot who thought she could do whatever she wanted just because she was cute, only to get turned on instead, is such a loser.
[P.S. Mostly daily life, with revenge as a secondary focus. The protagonist's character is a mystery: she gets stronger when she faces the weak, and even stronger when she faces the strong.]