Reikoku Koutei wa Hitojichi Oujo wo Dekiai-chuu Naze ka Nuigurumi ni natte Dakareteimasu

Ferlina is married to the ruthless Emperor Vald as a hostage to secure peace. However, an incident leads to her being possessed by an adorable stuffed animal Then, when the Emperor discovers her true form, she finds herself in dire straits -- or so you think... She wakes up in the form of a stuffed...

Source: MyAnimeList