Drenched by Magic by Katy Haye

Kyann won’t let the Emperor win, whatever it takes.
The souls of Axxon and Rey have been stolen, ripped from their bodies to leave the Emperor free to fulfil his evil ambitions.
But Kyann isn’t the frightened girl she used to be. She’s grown used to facing danger. If she has to venture into the underworld to fetch back Axxon and Rey’s souls, then that’s what she’ll do.
The decision is easy, the reality harder. Once they cross into the underworld, will they be helped by the goddess, or set back by the fabled soultaker?
Four kings, one girl, and a magical destiny that binds them.