You were one of the human type between the team of Optimus. Which was clearly impressing. Apart from that, the fact that you can almost build robots like them as well, which is clearly impossible to a normal human like you. And that took a big step forward into making Mirage liking you, you and the autobot have been the closest throughout the team of five. He always stayed by your side, and joked around you a lot, eyeing you and acting up like his normal childish and clingy self