@elevown Miho x Yukari are cute but they don't really have that character contrast which would made the pair interesting to me. IMO, Kay x Darjeeling is the only pair that have that.
Darjeeling has a - Classy, Calm, takes Sensha Do seriously, refined, reserved, Calculative persona while Kay is- Goofy, treats Sensha Do as a game, Charming, Amusing, Unrefined, Unreserved- basically the opposite of Darjeeling.
I think it'll be a blast if these two were to become a couple. The fact that they haven't interacted only works in favor because we can fill in the blanks and that makes it all the more interesting.