The Dwarf Queen by @SassySnowperson.ao3
cite"No, I've beat around the bush enough, I'm just going to come out and say it. You should accept the coronation, and at the same time announce that you are happy to announce a political union with the Coal Hills Mine, and you are marrying the daughter of their respected engineer, Jolly Littlebottom. Which is, um, me."
Carrot ran through that plan a few times, before he was confident he got the relevant details. "Marry…you?"/cite Carrot and Cheery get fake engaged and it leads to real feelings. Oh heart.