Ren is an adopted sibling of Yuma taken in by his family. On a trip they were on they found him all alone. Not wanting him there by himself, they took him in and raised him as one of their own. Even though Ren knows they're his adopted family, he couldn't be happier... even if Yuma does annoy him sometimes he loves all of them like his own family. But one day, a spirit named Astral would change their lives.