History and evolution:Edit
Carston was a great grand child of Emily Hawthorn 's Brother Sherman. Originally, he had nothing to do with Jason, but when I started sorting the time lines of the two stories I realized they would have to be about the same age. I also later realized they were cousins. and since Jason lived for a short time as a teen ager on ESM , they surely would have known eachother. I'm still sorting the overlap between these two and their friends and relations
Basically his time traveling grandfather leaves him a gift, which is a guitar with pictures painted on it. these pictures are coded instructions for how he will travel back in time to prevent the creation of Gaia/Leviathan . He does not manage to do so but does travel back in time, and his wife Sharae who looks like Emily Hawthorn ends up being consumed by Leviathan soon after it's creation because she is mistaken for Emily. He does not know hat happened to her, only that she did not return. Carston [aka San Heath] spends the rest of his life trying to get her back. Once he finds out what happened, he goes to the future and learns how Gaia would ultimately defeated and then sets about going back in time to create the conditions needed for Emily Scott-Harris to be born, so she can defeat Gaia and release Sharae's spirit from Leviathan.