Okay, so, at the end of NTN, John is drawing initials in the sand, right? They are as follows
JE- John ???
JA- John Alecto
JH- John Harrow (?)
So Blood of Eden, right? This can refer to the bloodline of humans who escaped earth, a proverbial Eden. Or it could be interpreted much more literally as those descended from someone named Eden. E.
JE. John+Eden
Anyway, what if John ended the world because his ex-wife was on one of those ships