Harapeko no Marie

The battle romantic comedy manga centers on a boy named Taiga and a girl who lives next door to him. He has always liked her, but when he finally gets the chance to talk to her she brings him back home as a human sacrifice to revive Marie Antoinette's daughter. After the ritual goes wrong, he wakes up in the princess' body.

(Source: Viz Media)
Note: Chapter count includes a bonus chapter in vol. 2, and the original one-shot in vol. 4.