I find it impossible for there NOT to be some kind of romance between say, a trainer and his female Gardevoir. Literally every aspect about this Pokémon would appeal to a romance story, from it being sufficiently humanoid and considered beautiful, to it's devoted and living nature. It would be akin to human/elf romances in fantasy or romances between humans/nymphs/goddesses in mythology. It is one of the few Pokemon that loving one would not be considered outright bestiality, due to it's design not being based off any animal. That's why Gardevoir has been such an enduring waifu over the years.