天は赤い河のほとり [Sora wa Akai Kawa no Hotori / Red River]

A sweeping historical fantasy romance, Red River follows a modern Japanese high school girl who is mysteriously transported back in time to the ancient Hittite Empire, where she becomes entangled in royal intrigue and a forbidden love with a powerful prince. Published by Shogakukan from 1995 to 2002, this 28-volume series is the defining work of creator Chie Shinohara, renowned for its meticulous historical research, dramatic political plotting, and epic, star-crossed romance. A landmark of the shōjo genre, it remains a beloved classic for its immersive world-building and emotionally charged story.