How Does 'Sharks In The Time Of Saviors' Incorporate Hawaiian Mythology?

To the citizens of Pierview, Taylor Yoshida is nothing more than a 16-year-old Japanese, home school, graffiti artist, delinquent, who’s always getting himself into trouble. However, Taylor harbors a dark secret from most of the people in town. He is the reincarnation of a kaiju; an interdimensional creature capable of ungodly abilities. But when more Kaiju attack Pierview, Taylor must shed his secrets and embrace his kaiju heritage to face these savage creatures and the secret organization responsible for their arrival known as Project Echidna.

She was lost, nowhere to be found. So, he began to find her. Little did he know she was just there all along hiding beneath the sea.(This story involves Philippine Mythology, but I altered some things for the plot to work out, thanks!)

Mia is a beautiful mermaid who has the power of telepathy, She can communicates with other mermaids and humans, plants and animals. She usually uses her powers to heal and make others feel better, everything changes when She is Kidnapped along with her sister Seila, by the Syrens, who are hald fish, half bird, the deadly enemies of the Mermaids.The Syren are monsters that feed themselfs of the heart of men. But they want one werewolf heart, Ignacio the Alpha Wolf's heart. But now his heart belongs and only beats for Mia.

Fairytales don’t always come from the earth... until her. 
 Mermaid legends are human fables, but beneath the waves, war is looming. A missing daughter is the only hope for a dying species. 
 Rescued during a typhoon, Galene finds herself in a new world amongst a dangerous species—humans. With no memories of her watery pasts, she doesn’t see the predators closing in until it’s too late.
 Stralath is a shape-shifting bounty hunter dedicated to keeping the peace in a violent universe. His earthly mission? To find the elusive mermaid who he’ll dangle in front of a dangerous oceanic pod.  Except Galene is not what he expected—she’s an innocent caught in a dangerous game of extinction. An angel who paints with color and smiles at the world.  She is easy prey, and Stralath abandons his mission, unleashing his brutal self to guard her heart and life. 

It was my honeymoon trip, but my husband's best friend insisted on going into the sea for shark watching despite being on her period. I reasoned against it, as sharks would go amok from the scent of blood, only for Heidi to snap at me, "You're just jealous I have a nice body! That's why you don't want me to have fun with your husband!" My own husband and his other buddies joined in too, brushing me off impatiently. "It's rare for us to hang out! Don't be a buzzkill!" "That's right! Hannah is young and beautiful. She should take pictures with the sharks." With that, they all went down the water despite my earnest protests, and her menstrual bleeding drew schools of sharks toward her right away. When I tried to help, she kicked me in the head, knocking me out and leaving me in the water as the sharks tore me to pieces. While I died under the sea in agonizing despair, Heidi, my husband, and their friends managed to get to safety. Once they returned to civilization, they reported my death as a drowning and pilfered all my wealth. While they rose to the peak of their existence, my parents, devastated by my death, both took their own lives. That was when I opened my eyes again and found myself back on the desert island where they were going for shark watching.

Charlie is a member of Black Diamonds, they hunt for these inhuman beings called mermaid. When the ship is attack one night, Charlie is pulled into a whole new world under the sea.