[Ren's brows both arch with obvious amusement at that, and he goes to flick Qingqiu's nose playfully (even if he doesn't quite reach it).]

You're pretty set on this idea even with how oblivious you are yourself, aren't you...? You still haven't said where this even came from.

[Ren's not entirely oblivious to any feelings he might have himself, but we're going to describe this situation as someone thinking they're the third wheel on a bicycle where the main two wheels are Kai and Aichi, except they're probably more like the third wheel on a tricycle where you actually need all the wheels.]