Often implies a sudden, romantic decision without much planning. The couple's spur-of-the-moment decision to run away with each other surprised everyone.
Pro Tip 2/3
Old-Fashioned Notion
The idea is considered traditional and may be less common in modern contexts. It sounds like a fairy tale for them to run away with each other and start a new life.
Pro Tip 3/3
Family Opposition
Sometimes suggests escaping family or societal disapproval or constraints. Disregarding their parents' wishes, they planned to run away with each other.