When she agreed to let a stranger sit next to her, there's no way she could have known what was about to happen.

According to the YouTube video description, user jellyfishdude's girlfriend Lindsey was returning from a month-long teaching program in Costa Rica. Rather than simply pick her up at baggage claim, however, he decided to arrange an unforgettable welcome for his love.
The ruse begins with a stranger asking to sit next to her, then quickly escalates as another stranger whips out a guitar. From there, Lindsey realizes that something is afoot and searches the airport for the man responsible. This is truly a romantic moment they'll cherish forever.