Hermie and Hestie never asked to be demigods.

Unlike others of their kind, they aren't interested in going on quests and being the center of a world-changing prophecy. But when Zeus learns of Apollo's vision--of the twins finding Prometheus, Zeus's number one enemy--the hunt for Prometheus begins.

If Hermie and Hestie don't find the Titan first, they'll have no chance of fulfilling their destiny or of surviving Zeus's threat against them. 

Hunting Prometheus Ebook