A brief description of the manga Kuchi ga Saketemo Kimi ni wa (2020 Short):
Miroku-san, a woman with a ripped mouth, must marry high school student Kouichi in order to maintain her existence. But this idea is clearly not to her liking, so they sign a contract. To break the engagement, she must scare Kouichi until he comes of age …
A three part short story.
2 manga Serialization: https://www.mangaread.org/manga/even-if-your-mouth-is-torn/