Somebody Please Explain What’s Going On Here! ~A Wedding that Began With a Contract~

Viola is the daughter of a poor noble. One day she receives a sudden proposal…but it’s for a contract marriage! Her new husband is the handsome and free super-elite earl, Lord Cersis. And he has a mistress! He’ll provide her food, clothing, and shelter, she doesn’t need to give birth to an heir, and she’s free to do as she likes…With terms like those, she can’t say no! Viola’s new life as a fake bride starts here!”
Can Someone Please Explain This Situation? / Can Someone Please Explain What’s Going On?! / Dareka Kono Joukyou wo Setsumei Shite Kudasai Keiyaku kara Hajimaru Wedding / Somebody Please Explain What’s Going On Here! / Dareka Kono Joukyou wo Setsumei Shite Kudasai! / The Duchess Of Rosia – A Contract Marriage? How Did This Happen!? / 誰かこの状況を説明してください! / 誰來說明一下狀況！~公爵邸的契約嬌妻