They’ve been best friend for years.
I mean, what’s sweeter than dating your best friend? You two know each others for quite some times, and I think it’s really cool to have someone who can be your best friend AND couple at the same time. I know that some of you might go with “They’re probably just regular friends” against this first point, cause, yes, I don’t know Khunfany personally. But guess what? You don’t either.