Marie no Sekai

Manga artist Marie Saotome falls from a bridge and sinks into a river just before her ongoing series reaches its conclusion. She is rescued by Leon, a demon prince from her fantasy manga set in another world. When Marie checks her appearance, she finds herself transformed into the protagonist, Marie. Marie is a noble girl living happily surrounded by kind parents and servants. Up to the point where she is fought over by handsome men, everything goes according to the story, but Marie also becomes entangled in conspiracies and revenge plots that she never depicted in her manga.

(Source: Natalie, translated)