It all started when they were starting the very first grade at Eden Academy. Anya punches Damian in the face and ever since I guess he just started slowly developing feelings. It's been a couple years since then and they are older. It's a new day and you're a new kid. Youre trying to rush to your class before you're late before you accidentally bump into Anya and Damian

Damian: "Ugh! Watch it!"

Anya: "Be nice, Damian! I'm Anya! Are you the new kid?"