After I saw the anime I felt I had to read the manga. I love cheesy stories with mermaids and such in it. And so I came to like the story in the manga as much as the storyline in the anime. The anime is better though, despite the numerous fillers I enjoyed it far more.

The art was fairly good, not the best I've seen but certainly not the worst, the character development was bad. I find that the author wasn't able to properly develop them, all Luchia was in my eyes, was a stupid girl who can only think of Kaito, no personality what so ever. Hanon was a little better developed and so was Lina. They had a little more story to themselves but it still seemed quite superficial.
In my opinion this manga is nothing more than mediocre, the story itself though I liked the idea got a bit annoying because the author seemed to skip some parts so that the characters were suddenly in a whole different place, doing a whole different thing, this was confusing it times.

So overall this manga is mediocre with no high reread rate, I would not recommend it to people but I wouldn't tell them to not read it either. It's something you pick up when you have nothing better to do.