Kaori is 18+ so there's no need to age her up.

Note: When I saw her in the anime, I instantly thought of Tohka XD, she looks like her twin sister, can you blame me for thinking of Tohka.

Plot - Academy City was quiet, save for the footsteps of Kaori walking the empty streets, her sword by her hip as her pale skin covering in goosebumps as the night air kissed against her skin. She was a Saint, she was hunting for something or someone.