The One to Whom I Owe My Soul (Percy Jackson...
Annabeth and Percy are happy as can be. (That's your first clue that things are going to schist).
Gaia has been defeated, the camps are at peace, Annabeth and Percy are going to college in California, and monsters have rarely been around to make their lives hard.
Could life get better?
Yes...yes it can.
A very ancient, very old curse is cast. One meant only for children of Poseidon/Neptune. Percy finds himself struggling for survival, as Annabeth embarks on a quest to find a cure to this curse before Percy is gone...this time, for good.
But time is running out.
The countdown for survival has begun.