>>33634005>>33634011>>33633898Stop applying real life rules like an autist for a moment and consider it as a work of fiction for children, which it is.
Unlike every other girl in the entire animated canon, Serena was blatantly in love with Ash from her first episode and that lasted until she left, with more serious moments happening the further the series went on. They built up the anticipation with teases in episode titles, (First Date, anyone?) to yanking the characters chain in-series (Dance Episode). In the climax of XY (&Z), tells him that she's his goal, and that she'll be"much more charming the next time [they] meet". And then she kisses him on her way out. Ash didn't freak out, he just smiled and said "see you later, Serena!"
In a children's show where they have never had a serious kiss on-screen before or after, where a characters singular motivation was being in love with the protagonist, and where so much focus, both in the show and outside it, in the promotion, have pointed that out, this is basically impossible to top. Pokemon lives in the status quo, so no one seriously expected Serena to stay after her series ended. But this is the next best thing, and until they top it, Serena is the defacto Ash winner, simply because her crush got the most focus.
It may not be happening onscreen right now, but we're meant to assume that once Serena returns to Ash (a moment probably never animated) they'll get together. And that's what makes it the closest to a canon Ash-ship.