I just finished reading Gaudy Night by Dorothy Sayers:
In the book Lord Peter Wimsey continues proposing to the love of his life, Harriet Vane, on an average of once every three months over a period of five years. As they are both classically educated Oxford graduates Peter takes the opportunity to practice his Latin with her as he proposes.
One first of April, the question had arrived from Paris in a single Latin sentence, starting off dispiritedly. "Num . . . ?"—a particle which notoriously "expects the answer No." Harriet, rummaging the Grammar book for "polite negatives," replied, still more briefly, "Benigne."
Note: (Benigne – no thank you.)
". . . But I will ask you now, and if you say No, I promise you that this time I will accept your answer. Harriet; you know that I love you: will you marry me?"
. . .
They passed beneath the arch of the bridge and out into the pale light once more.
She stood still; and he stopped perforce and turned towards her. She laid both hands upon the fronts of his gown, looking into his face while she searched for the word that should carry her over the last difficult breach.
It was he who found it for her. With a gesture of submission he bared his head and stood gravely, the square cap dangling in his hand.
Note: (Placetne – Does it seem good?/Is it agreed?)
(Placet – It seems good./ It is agreed)
Maybe it's just me and my love for languages. But this is the most romantic proposal I've ever read.