Mermaids are nymphs that fell in love with the sea. But unlike Naiads or dryads who’s children are nymphs, mermaids produce more mermaids. Because of this they are the most abundant of the nymph group.
They have their own island called Neep, the island is a series of caves and rivers that allow them to reach almost every point of it while never leaving the sea. Similar to naiads they collect treasures, but unlike naiads they never give them back, keeping everything for themselves hidden away in holes in the caves.
Mermaids seem to never mature, they get up in the morning, check their hoard of treasure, hunt some fish, play until the sun sets then sleep. They have little goals in life and rarely leave the island.
They often get crushes on humans and other species but never maintain a long term relationship, much preferring the short term benefits.
Despite all of this their love for treasure and lack of understanding about value makes them a valuable resource for The Union.
There is an agreement in place that every child or sailor lost at sea that the mermaid’s return alive they will receive a crate of ten glow in the dark potions. For every body they find they will receive but one.
The issue is they are not very loyal and can be bought by other bordering countries to spy. Because of this you must be careful what you say to them.