Deep Sea Dragons, as their name suggests, spend most of their time in the darkest depths of the sea. They have a bioluminescent dorsal spine that serves to attract prey and communicate with their own kind. As with many deep sea animals, they generally eat whatever they can manage to bait. They rarely leave the ocean floor, surfacing only during breeding season. When they do choose to travel to the shallower depths, they avoid bright lights and will only come up far away from shore.

Dragons are highly-intelligent reptilian creatures that—from a human perspective, at least—appear to live forever. Many different varieties of dragon exist, each with their own unique qualities, habitats, and behavior. Adolescence in dragons is usually marked by the growth of a hatchling’s wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. In Galsreim, dragons and humans coexist peacefully.

Kokoro Yamada a female dragon that dislikes boys so she never comes out of the sea for mating season. Even though most females who dislikes boys like Kokoro are mature enough to do mating season. Kokoro was forced to do so and had a child. Since that forced upon mating she liked boys better and better. That dislike healed now her illness didn't yet. Her illness isn't life threatening, it is actually the opposite. She can live longer than other dragons. She has seven hearts. Other dragons bullied her, but one female dragon stood up for her. She said,"It doesn't make a difference if she has 7 hearts does it. She has 7x the emotions everyone has. When shes feeling pain it is 7x worse. So stop,". She made an impact in her life. So she is now not afraid to say," I'm Seven Hearts,"