When she accepts a walk-on role in an historic action film, the last thing nineteen year old Emmi Maeda expects is to be zapped to the Kyoto of 1864, via an antique mirror, but she is. She soon finds herself chased, attacked, and practically seduced by sword wielding samurai and put on the marriage market by an ancestor.
On the upside, her arranged husband, Kaemon, is a hunk (and a real live prince). On the downside, Emmi accidentally kidnaps the future Emperor of Japan, and Kae might have to kill her then commit ritual suicide to atone for Emmi's misdeed.
Time travel to 19th C Japan Seemed to have more heavy petting/sexual details, than the typical YA book. However heroine was 19yo, so it was not totally inappropriate.