Somebody Please Explain What's Going On Here! ~A Wedding that Began With a Contract~ is a Manga/Manhwa/Manhua in english language, Manga series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.nl fastest updating comic site. The Summary is

[PocketComics Ver]
"Will you please become my fake wife?"

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!"