Contract Marriage

Woman wakes up in the body of a Duchess already in a contract marriage. She's treated miserably, so she sets out to improve her life WITH TEA!

Priscilla enters into a contract marriage with the ML after turning back time in the hopes of avoiding the horrible future she'd lived through. I'm really enjoying this one.

Adele is contracted to act as Felix's fiance to chase out a horrible woman. Adele is AWESOME! Hands down one of the BEST leading ladies in a story like this I've read (except how she gets Felix to confess, that feels too much like manipulation for me)

Our FL wakes up from a "vivid dream" and realizes that it's her future. Desperate to change it, she enters a contract marriage with the most feared noble. This webcomic shows a married couple actually engaging in sexual intercourse, and I must say, it's refreshing especially for this specific set up, where the sexual part of a married couple is usually skirted around.

The FL was the captain of the holy knights (a woman) and has her soul transported into the body of a "weak and frail woman" in the hopes of weakening the FL. Thankfully she was always a female, so that doesn't both our FL. She makes enters into a contractual engagement to have her identity revealed.

FL, who awakens as the murder victim from a book she read in a previous life, enters a contract marriage with the ML in order to avoid dying at the hands of her previous fiance. This changes the course of the plot of the book, and of course leads to new relationships being developed that never happened in the book.

A homely scholar is forced into a contractual engagement with the emperor to ward off attacks towards i think his sister? I don't know, it's a bit confusing why they need her to be his fiance... Still, it's interesting and I'm looking forward to more.

FL lives a miserable life thanks to her fiance and ends up dying trying to please him, but wakes up a year prior to it all and decides to do things differently this time. To change her fate she enters into a contractual marriage with the ML, who is the only person with equal influence to her former fiance.

So... she has THREE fiances, which also act as he guardians via an international law/contract? Sure, why not I'll put it here.
Despite the previous sentence, I really do LOVE this manga, I honestly can't recommend it enough. If you love strong, independent women, this one is for you. Her fiances have ZERO control over her and it's awesome.

So, not a contract technically, but she still seeks out the ML to avoid her bad end, proposing to him for both of their benefit. I'm putting it here with the knowledge that it's pushing the limits.