Vampires. Hasn't Purim already proven herself here? She helped take down at least two vampiric bosses, and that Thanatos fellow was a lifeforce-sucking lich, which is close enough really. Brahms might allegedly be a good vampire, but he's suffering the same fate as the rest against one of the most relentlessly anti-physical mages around. Defender buffs Purim's defense to ridiculous levels, and Lucid Barrier can null Brahms' strikes entirely, rendering the poor vampire completely worthless. That's assuming Purim wants to even bother defending, of course - as a creature of the night, Brahms suffers an elemental weakness to Lumina's Lucent Beam, so promptly spamming the holy flashlight should finish the fight just as easily here against Brahms' subpar magic defense.