The Gatekeeper's Challenge (Gatekeeper's Saga #2)

Ten agonizing months have gone by since Therese faced off against her parents’ murderer at Mount Olympus, and she suspects Thanatos’s absence is meant to send her a message: go on with your life. She tries to return Pete’s affections even though her heart aches for the god of death, but when Than shows up to take her hamster’s soul, she becomes infuriated when he says he’s “been busy.” In cahoots with her new friend, who's gotten in with the Demon Druggies at school, Therese takes a drug that simulates a near-death experience, planning to tell Than off so she can have closure and move on, but things go very, very wrong.

Eventually she learns Than has been busy searching for a way to make her a god, and he’s found it, but it requires her to complete a set of impossible challenges designed by Hades, who hopes to see her fail.