On the Origin of Species: Luvdisc
But we're not concerned with popularity here! Even the weakest, most overlooked Pokémon can have an interesting origin story to tell, and Luvdisc owes its existence to two rather different creatures.
The origin that was initially most obvious to me (and I suspect to many other players) is arguably the less important of the two when considering Luvdisc's design. It did, however, heavily influence this Pokémon's moves. The ability to learn moves like Sweet Kiss, Attract and Captivate - combined with Luvdisc's characteristically prominent, pursed lips – points towards that most romantic of fish, Helostoma temminckii, commonly known as the kissing gourami, or kissing fish.
Kissing gourami are large, freshwater tropical fish from Southeast Asia. They can be found in two colors: a green variety mostly found in Thailand, and the more commonly seen pink variety, from Java, an island of Indonesia. The pink kind are pseudo-albinos (meaning that they mostly lack pigment) and are seen so often because they make popular pets. The green variety is actually much more common in the wild.
The species is part of an unusual group called the anabantoids, or labyrinth fish. This suborder, which also includes such notable members as the paradise fish and Siamese fighting fish, consists of fish native to slow-flowing waters that are low in oxygen. These fish have a labyrinth organ: a lung-like structure that allows them to get oxygen directly from the air, in addition to the usual method of extracting it from the water via gills. This is a great adaptation for their low-oxygen environment, and even lets the fish survive out of water for short periods of time, though it means that such species always need access to the water's surface in order to take a "breath" now and then.
Those lips are actually covered in tiny teeth, and when the fish appear to be kissing surfaces such as rocks, they're using those teeth to scrape off algae, which is one of their sources of food. When two fish kiss each other, they are actually fighting: the kissing individuals are almost always two males competing for dominance. While the fighting itself is harmless, some younger males can be bullies, constantly challenging weaker fish, and ultimately end up killing their rivals through stress. They can also indirectly kill other fish due to their habit of feeding on their mucus coating that would otherwise protect them from infections.
If all of this seems a little darker than what you'd imagined for the origins of the innocuous Luvdisc, then worry not, because there is a second species that inspired this Pokémon, and one with a more direct influence on Luvdisc's appearance. And luckily, this species is positively adorable.discus fish. These fish are part of the large and extremely diverse Cichlid family, and can be found in the Amazon River basin. Discus take unusually good care of their young, sometimes being likened to mammals in terms of their dedication, and both parents are involved with the process.
For the first few weeks after their young hatch, both parents remain close by, protecting and feeding their offspring. The feeding happens via a nutrient-rich mucus secreted by the adult fish, and just like the mucus coating mentioned earlier, it contains antibodies to fight off infections, meaning that this immunity is passed onto the offspring. When one parent has had enough, it "flicks" the young to the other parent, who takes over feeding. This behavior has been likened to mammals suckling their offspring. They even go through a weaning process: after a few weeks have passed, the parents start swimming away from the young fish in an effort to encourage them to forage for themselves.
Luvdisc’s overall shape - and, indeed, its name – is evidently derived from these fish. Discus have a flattened body, roughly circular in shape, and the rounded fins of many species do indeed make them resemble the heart-shape used for Luvdisc’s design; the only real exaggeration is the removal of the tail.
So how does Luvdisc fare as an avatar of love and affection? The first of its influences, the kissing gourami, is superficially “romantic”, but is actually the result of us humans mistaking fighting for affection. The discus fish was likely just intended to lend its heart-like shape to the design concept and nothing more, but it’s easily the more affectionate of the two fish, displaying a level of parental care and cooperation that’s pretty much unparalleled among similar creatures. Discus don’t mate for life (though some pairs will stick together for a long time) but if I were forced to choose a fish to describe as “loving”, I think the discus would be it.