Isaac and Rynn are brothers. Rynn is in a relationship as well as Isaac. They're living a fairly normal life. However, Rynn and Isaac feel like they shoudn't be there.
Esne is revealed to be their mother. She sent them to Earth and intended for them to only be there until they were 10. There was a civil war that arose in the Astral realm- so they were forced to stay nine years longer .
Rynn begins to Astral project and communicate with Esne. Isaac is meant to take the thrown-- Isaac is heavily opposed to this notion, he doesn't want to leave Matt. Rynn decides he'll take his place.
Esne ends up showing that she is old and hurting and needs to have her essence destroyed in order for her to fully give ownership to the astral realm to Rynn. She "dies".