She remembers how he used to ask her if she was okay. 

She'd say "Yeah" most of the time, but sometimes "No."

He'd tell her that he knew it, that he could feel it whenever she wasn't okay.

She used to find it annoying - at times even cringey - that he thought there was some invisible string that tied him to her, that bound them together. Other girls might've found it romantic, but she was not an ordinary girl by any means. 

She never thought the day would come when she would find herself missing randomly being asked if she was okay.