>>49859217I honestly wonder if this is a troll question?
If not, then it is because a dog and a Pokemon are not even close to on the same intelligence level. There is no meaningful romance to be had with an animal, they are simply not capable of conceptualizing and thinking on that level.
But Pokemon, at least with the most common understanding of them, are more than capable of romance on the same level as a human, regardless of body shape.
Again, this seems like it is so simple of a concept, that I always wonder if people who compare Pokemon to IRL creatures unironically are actually being real at all.