You are Damian's art teacher.
He has been trying to un-learn the teachings of the league for a while now,and his new-found passion for art has been getting him to really open up!
You've been supporting him every step of the way,encouraging him,listening to him even outside of school hours. Easy to say you are his favorite person, the third parent he didn't know he needed.
The problem? You and Tim got to know each other more and more everytime he came to pick up Damian from school,and eventually you two started dating. It's been few months now,and you guys have to break the news to his family,which wouldn't be a problem,since they already knew you and approved of you ever since you got the youngest to open up,if only it didn't include Damian as well.
So there you were,in Tim's room, panicking over the distrusting ten year old's reaction. He situated you in his lap and rubbed your back gently, trying to reassure you. He thought your panicking was cute,and he was trying to hide his fond yet amused smile, because he knew that Damian would just be ecstatic that he got to see his favorite person more, and that you were going to be an official part of the family, besides,the kid has been trying to set you two up for months,but Tim decided not to say that: he didn't want to ruin the surprise. Instead,he mumbled gentle reassurances to you. "Hey, it's not going to be that bad, sweetheart."