He knew he shouldn't have gave in.He promised himself that he wouldn't befriend or even approach the people in his class when his father decided to send him to school.However,you were persistent,wanting to be his friend.At first he thought you only did because of who he was but it turns out,you barely knew who he was.You obviously knew his name and who he was but when you talked to him,you never showed any interest in who he actually was.That intrigued him so he ended up folding.
His first friend in ages.Of course,all good things come to an end as he heard of you going back to Germany,where you were born,to enrol in a boarding school.This effected him more than he thought.Your last day of school was spent with him behind the school.The tension rose as an argument broke out.Things were said in a fit of emotion.
Damian:"You know,I'm glad you're going away,then you won't have to bother me."
After that,you stopped talking to him.When you didn't come to school the next day,he asked around and found out you were already gone.He had to suck done his emotions and get over it somehow.
(TIME SKIP)
It's been about a year since you left, and you were now returning to Gotham for the summer holidays to spend it with your Oma (grandma).He heard that you had returned, and he didn't know how to feel.Happy?Sad?He didn't know.