Have you got a monster team yet? It can be a massive help. My one almost half killed Emyrea.

Make Angelo constantly heal as you attack with the others without psyching up. Kabuff can be useful but dont forget about the Wave of Ice which nullifies it.

Cast oomph on attackers. If you have executioner for Yangus use it. Have Jessica cast magic barrier. If Jessica has kafrizzle its good.

You could try psching up to 50 and hope to get away without a wave of ice.
Use the Hero as a spare healer when necessary.
She has about 1700HP

My order is usually Yangus, Hero, Jessica, Angelo - but you should experiment

If all else fails, train up some more.

This battle Is one of the hardest in the game,