The Mermaid Star [editing!]

Underwater Book

I know what you're thinking. How come my dad, a merman, had a book? Well, I was thinking the exact same thing. We all finished up our Sonic; Eric and I ignoring the looks from River and mom. She drove us home, and she got the book out from under her bed. It had a seaweed cover, and it looked like the inside was seaweed, too. I opened it up. The first page was... a warning. It read:
If you, the reader, is not of mer-blood, then beware, for this book is of mer species only.
I shot Eric a look of bewilderment. "What?" Eric shrugged. "Why not? I mean, we are 'of mer-blood', right?" I turned the page, and continued.
The Basics
Mers are the most powerful species on Earth. Most with the ability to heat, freeze, or manipulate water in some form, others able to do two or more. Mers could easily take over the Earth, but choose not to, as their children are human until their thirteenth birthday. After the mers thirteenth birthday, whenever they touch water, they transform. Most mers marry a human, then leave the human to care for the children. Only one child in the family can be a mermaid/merman.
I turned the page.
Blood Mates
-Blood mates have the same blood.
-They also were born on the same day.
-When blood mates first meet, their eyes switch color.
-In example, if the mermaid had brown eyes, and the merman had blue, within 24 hours of meeting, the mermaid would have blue eyes and vice versa.
-Their eyes will stay like this until both realize they are blood mates forever.
-When blood mates have their mer-child, the child is guaranteed to live until their 13th birthday.
-The blood mates cannot have children with anyone but their mate.
-After blood mates realize they are, each time they see each other, their eyes change to match their tail color for a few seconds.
-Once every ten years a blood mate is human.
I continued on.
Having Merchildren
The mermaid is pregnant when a pearl appears in the middle of her hand. No pain occurs if she stays in her mer form.
"Okay, last page."
Semi-Mers
Occasionally, a human child will drown and an underwater witch will enchant them to become a mermaid. Another way for a human to become mer is if they eat a scale off of a mermaid with more than two powers tail. The only way to distinguish between a semi-mer and a mer is their tail. Their tail will always be black, no matter how hard they try to hide it.