Cater is very good at reading a room and reading people, he knows when people are angry or when people want to be left alone...That would usually scare him off but here's the thing...He likes you so he ignores those social cues...

He doesn't know when he fell for you but he did so he started with posting you on all of his social media accounts and changing his status...Then he started giving you gifts and smothering you with love...You caved and that caused him to give you a promise ring...