Thor, Loki, and any other Marvel character that appears in this story belongs to The Walt Disney Company and Marvel.
The title are lyrics from the song "Two Birds" which belongs to Regina Spektor.
Volume One
Humanity had been cursed with immortality.
For 70 years, anyone born in 2030 and past that year, they were immortal. People tried to find the reason why humans were being born with immortality, but no reason couldn't be justified. And so the 70 years went by and numerous children were born with immortality.
Thor and Loki Odinson were one of those children.