Pandava Quartet book 2
Spoilers ahead for the first, especially as it picks up after the cliff-hanger.
With a zombie breakout in a magical market and a quarrel about who is a thief. The boy Aidan established to Brynne that Aru was not the thief, there was a shapeshifter involved. Alas, the higher-ups did not agree, and it was the bow of Kamadeva, god of love, and its misuse is causing the Heartless, which they had mistaken for zombies.
It involves untold stories, what Aidan wants from Kamadeva, dogs of nightmares, Oreos, many accounts of gods doing wrong things, the threat of losing their memories of each other, a Otherworldly mall, some very dangerous cows, someone not giving them a lot of help, and more.