Steve Rogers is the king of the city. When he proposes an engagement between Stark's daughter and his stepson, Tony reluctantly accepts. When you offer yourself up in your little sister's place, Steve suddenly isn't so sure you marrying Roman is a good idea. After all, your heart does flutter so prettily whenever you and the king are alone together. **This story contains mature content between two consenting adults over the age of 18** Story is a reader insert without the use of y/n. Story does contain mentions of cheating though the main characters are faithful to each other. There is also a brief mention of unwanted groping. Story also contains some dark elements such as murder, assault, etc. It's a mafia fic y'all.