There is a mutant in the Marvel universe called Domino. She has the ability to control probabilities. Sometimes people say she can control luck. Domino was a character in Deadpool 2 for those of you unfamiliar with the comics. Jen, a girl in our friend group back in college, was a huge Marvel comics fan. She actually got me started on my love of comics.
One day we were driving somewhere, and as I pulled into a parking spot very near the door, I heard her say, "See! I told you." After some questioning, I learned that Jen had been watching me for several months. According to her, things went my way more times than not. She even went on to claim that people I liked shared in this good fortune and that people I didn't like had bad luck. There were even examples offered up as proof.
That day, my friends dubbed me Domino and began to attribute things that happened to the "Domino Effect". Since it is one of the nicer names I've been called over the years, I decided to own it and have used the name and phrase ever since.