
A while back I was blobbing around on Rumic World and saw this, and thought it looked interesting. Basically, the plot follows Mana and Yuta, two humans who have eaten mermaid's flesh. Most people who eat it are either poisoned or become "lost souls" (a.k.a. they turn into monsters), very few survive to become immortal. Most of the story (so far) are incidents where they meet people trying to become immortal (or getting it for family, ect.) or dealing with the problems of eating Mermaid's Flesh. It's one of RT's more serious stories, I ended up crying at one point. Really, really sad. I seriously doubt cathy will ever watch this, so I'll cut and slightly edit Wikipedia to give an overview of the first episode, as I cannot be bothered to review it myself. Sorry.
Anyway, here's Wiki:
Around midnight, a fifteen year-old girl named Mana watches out the window with the moonlight along with a mysterious moaning ghost-like noises. She orders and old woman looking after her to stop the noises. The old woman tells Mana that there is nothing they can do to stop the noises. The noises only happen when there is a full moon or a new moon out.
A traveler named Yuta asks for directions to go to the mountains. He is searching for a mermaid.
Later at dusk, while Mana is eating her dinner, the old woman complimented her as the most beautiful woman that had ever been in the world, but Mana was tired of hearing those compliments so she threw her entire meal at her.
At night, Mana lies in bed, having flashbacks that the old woman and the other women from the village adopted her as a little girl, remembering all they do is carry her around, never letting her walk and go outside. She wishes she can walk. Meanwhile, the old woman calls a meeting about Mana. All the women there have the same face. The old woman announces that this is a time for one of the women's sacrifice. They chose a woman named Ayu, as the women said that Ayu has lived the longest.
In a hidden cave, Ayu takes off all of her clothes and enters the pool, her legs turn into a tail, and then the women kill her. One of the women then cuts the mermaid flesh out from the tail.

The next day, in the afternoon, the old woman brings in Mana's lunch with mermaid's flesh as a dish. Mana asked what kind of fish is it and Baba told her that this is the rarest fish the women had caught. Mana then slowly eats the meat, enjoys the rich taste and eats more and more. She catches Baba's sudden expression and throws her bowl of rice at Baba for staring at her.
The women were full of excitement when they hear that Mana has eaten the mermaid's flesh. But their happiness was interrupted when they hear that a man has entered their side of the mountains. Yuta arrives on top of the mountain is startled to find so many women living in such a deserted place. They suddenly kill Yuta and throw his body down to the pit of a cave with the remains of Ayu. Within a few hours, the tribe have decided to take Mana outside, when Yuta (having revived) bursts into her room, carrying the carcass of a mermaid. The women try to attack him again. Yuta wastes no time on taking Mana hostage but discovers that her legs were locked. They hid in the cave with Yuta while he explains his story to Mana to why he is searching for a mermaid: He is an immortal of five hundred years, in desperate need of regaining his mortality by meeting a mermaid.
Suddenly, a horrifying creature called a Lost Soul attacks Yuta and Mana, who escape out the cave. Yuta leaves Mana to talk with the women and discovers that the women in the village are in fact mermaids who want to regain their youth by eating an immortal (i.e. Mana)
Yuta and Mana hide in the cave again, but Yuta is attacked and posioned. Mana spits the poison out of Yuta as he passes out. The old woman decides to flood the area, to drive them out to the ocean where they can easily catch them and devour Mana. As they are pushed out to sea Yuta sees dozens of mermaids coming to attack. Mana and Yuta escape from the sea, but the old woman follows. She tells them they may as well be killed now, as it would be far less painful to die quickly than to be immortal (as they now are) and to live forever. She then tells them that she too is an immortal human and that she will stay with the mermaids until the end of time.
It's looking to be really good - there are some bits that seriously surprised me. I was really surprised it was ON veoh, I thought it'd be pretty unknown.