In this ay, Edd, Matt, Tom and Tord are merman, and the girls (Evelyn, Molly, Susan and Annya) are ordinary people (except that Molly is half-human half-mermaid).
Girls work in the dolphinarium / oceanarium. And sometimes boys swim to them. They declare their appearance in different ways. Edd just swims out to Evelyn and sits next to her. Matt does the same, only for the effect of surprise he hugs Molly. Tom does according to the Edd's method. And Tord abruptly grabs Annya by the leg and drags her under the water, and bites her neck until it bleeds, and then lets go and swims out.
Girls have a necklace (a gift from one of the boys) with which they are able to turn into mermaids. So, performances with mermaids have been introduced in their oceanarium / dolphinarium (boys sometimes take part, but it’s a problem to make Tord participate there, but if for fish, he will agree, but only if he was not deceived, because he will be offended).
And now for the mermaids.
Depending on which group the mermaid / merman belongs to, this affects his physique, character, and so on.
There are only three groups: vegetarians (Edd belongs to this group, but sometimes allows himself to eat fish), omnivores (Matt and Tom (Tom is an intermediary between omnivores) and predators) and predators (Tord belongs to this group). But all mermaids / mermen can eat human food (but mostly they eat fish and algae).
Also, mermaids/mermans are able to shed their tail, and it turns into legs (usually for camouflage, and sometimes for other purposes).
Most often, mermaids are born as normal children, but from adolescence, they begin to show signs that they are mermaids. For example, in Tord this was manifested by the fact that he began to eat aquarium fish, although he tried to do something about it, but then he ate them all (and so on).
The appearance of mermaids / mermans is familiar. Instead of legs, a fish tail, fins on the elbows, gills on the neck (this is not official), scales on the chest (only for girls).
Belongs to the group of vegetarians, but sometimes can eat fish. The teeth are even, has small fangs. A slightly plump body (not visible in the figure), leads a less mobile lifestyle (because it feeds mainly on algae, and almost does not hunt fish). Friendly by nature, able to trust. He considers Annya his sister (well, they are still half-siblings, but when he went to live at sea, he was considered dead). In love with Evelyn.
Belongs to the group of omnivores. The physique is shapely, more active than Edd. The teeth are even, the smallest fangs. Mostly lives near corals. Matt likes beautiful things and collects them. His collection contains both marine items (including pearls) and human items (especially mirrors). Similar in character to Edd. Even more friendly and trusting. In love with Molly.
It belongs to the group of omnivores, although in fact it is an intermediary between omnivores and predators. The physique is similar to Matt. The teeth are slightly sharp compared to Edd and Matt (although not the sharpest). Likes harpoons. Of course, Tom won't be Tom if he doesn't hate Tord (the opposite day doesn't count). He met him when Tom came to Norway for the holidays (he was then still a human), and Tord had already become a merman, and sometimes began to steal fish from fishermen. He also started stealing fish from Tom. At first he did not notice, then he noticed and became annoyed. The last straw was that Tord tried to seduce Tom's cousin Molly and drown her. Then Tom wounded him with a harpoon in the tail. Tom is less friendly, and at first his trust must be earned so that he understands that no harm is meant to him. But gradually he falls in love with Susan.
Belongs to a group of predators, so he is the most active of the guys. Tord's teeth are the sharpest, and are able to pierce human skin. But he's not just a predator. For most of his life, Tord lived in Norway, and then in the Norwegian Sea, and since the climate is not the warmest there, Tord is quite resistant to cold (he later sailed to the British Sea and met Edd).
But so during the hunt, Tord has a cold mind, and when he is very hungry, he will hunt until he quenches his hunger, even if he feels exhausted.
Since Tord is a predator, he needs to be agile, fast, hardy and strong. So he has a pretty flexible and strong body. And in terms of physique, Tord is quite muscular (don't ask why).
Also, Tord had an idea (except for stealing fish), according to which he seduced girls (well, what, his body is quite attractive, and the girls were led to his trick), lured into the water (where he turned back into a merman), and a little later drowned their. The last of his victims was Molly, but Tord did not have time to drown her, as Tom ran in, wounded Tord with a harpoon in the tail (there is a theory that Tord has a scar in that place, but this has not yet been proven).
Tord likes extreme situations (storms, etc.), although Edd often warns him that it could end badly. But Tord absolutely does not care about this, he loves extreme situations, that's all.
By nature, Tord is the most unfriendly and absolutely does not trust people, and it is very problematic to earn Tord's trust. When a person approaches him, he bares his teeth and begins to hiss menacingly. Sometimes this can end up with Tord drowning the person in question. Even Annya found it difficult to start a friendship with Tord.
And now how could our couples meet:
Edd was sitting and basking in the sun (it was May) when he saw Evelyn just walking along the beach. She also saw him, and at first she was surprised, because before that she had not seen a merman, or even a mermaid. But be that as it may, Edd decided to meet first. He swam up to her first, and struck up a conversation. They talked for a long time, and then realized that they became friends. Evelyn began to visit Edd every day, and one day they realized that they were in love.
Once Molly lost her ring (it's not a wedding ring, it's a regular ring) at sea. She found him in the sand, next to the stones, and did not notice how she sat on the tail of Matt, who was looking for new beautiful things in his collection. At first she was scared, because her last time with the merman ended badly, and she wanted to beat Matt. But he began to whimper and yell "Not the face!" and Molly was surprised at first that Matt was different from Tord, who nearly drowned her. She became more friendly to Matt. And a friendship began between them.
She was supposedly shipwrecked when she and her parents were traveling from America to England and she almost drowned, but was rescued by Tom, who took a liking to her. At first, Tom did not particularly trust her, like her, but Susan was the first to take a step towards friendship, and then towards love.
The reason she started working at the aquarium/dolphinarium was because she was kicked out of the army for some offense and Molly offered her a job. Annya liked sea animals and fish. As a child, she heard fairy tales about mermaids, and considered them fiction, until she met Edd, who was believed to be dead. Annya is a little jealous of Edd in terms of the fact that he has a tail instead of legs, and wants to become a mermaid. But she manages to feel a bit like a real mermaid when she gets the opportunity to participate in the show as a mermaid. True, she almost suffocated in the water, which is why she was temporarily suspended from work due to poor health.
She was walking along the beach when she saw Tord, washed ashore after a recent storm, and tangled in a fishing net. Annya decided to help him, but as soon as she came closer, Tord bared his teeth, and began to hiss menacingly, and began to try to get out of the fishing net, but he only got more tangled in the fishing net, and this fishing net only fit more into his skin. Annya laughed a little, and yet helped Tord.
Tord treats Annya with distrust, and reluctantly comes out to talk with her. But then he starts to thaw and is more willing to talk to her. He starts complimenting her about how beautiful she is and how she would be if she were a mermaid. And at one point, he will give her a necklace with which she can turn into a mermaid.
Don't ask about that. It's cringe.