jon is kyungjae's ex so they probably knew of each other at some point! maybe they could've been friends from before the two dated/broke up which was feb-april. for ways to meet jon would be the type to attend an architecture showcase or even order one of youngjae's hand made pieces (he's really into that stuff and would be full of Questions). jon is on the extraneously realistic side of things when it comes to romance so youngjae could balance him out there, or jon can crush his dreams (gently)