You remembered wrong. She was a young girl who'd already been living in Japan and attending school. She was lonely and insecure, due to Japanese xenophobia, so she practised martial arts to help with that. That was when she met Hanako's dad.
Oh my goodness, it's actually been 4 years and 200 chapters already! I love how the author really tried to make the atmosphere and tone of the 200th chapter special. Love it!
My dark mind is imagining if this was an edgy male protagonist, he'd destroy the entourage and while the queen was pissing herself, "this is what you get for dressing like a slut and threatening me..." before we get some hot action happening xD.