Let’s debunk a myth: When two characters declare exclusivity in the first chapter or the first 20 minutes of a movie, the audience asks, "Based on what?" You haven't earned the stakes.
Second, recognize that your relationship doesn't need to follow anyone else's storyline. Some couples become exclusive after a week; others take months. Some know immediately they've found something special; others grow into love gradually. Neither timeline is more valid or more romantic than the other.
They thrive on obstacles, yearning, and grand gestures.