Imagine your OTP - Person A goes to Starbucks quite frequently and plays the piano there, which gives the coffee shop a soothing tone. (It can be set in a bookstore, idk my bookstores have Starbucks in them.) Person B is a regular comer for both the coffee, and the soothing music that's there everyday. One day they realize that Person A isn't there, and begin to panick, worrying that something happened. The next day, Person A comes back, and Person B gains the courage to talk to them. Smooth flirting ensues and boom- instant relationship.