There's all sorts of potential for headcanon around how aging, evolution (or the negation thereof) and non-sport orientation works for Pokémon. This picture seemed a little odd at first since the Kirlia has a bit of a stilts look going on, but upon further thought it's entirely possible that they're just getting on in years, or approaching the evolution point - most Gardevoir aren't much less stilt-legged, really, it's just more hidden.
In any case, it's an interesting take on Kirlia and a neat transition point. :>
