After you enter Fei'Yin, a Notorious Monster named Miser Murphy spawns near the Dry Fountain at (H-8) on the first floor. He is a ghost NM with an occasional additional effect of drain on his regular melee attacks. This drain can do upwards of 600 damage to a player, restoring the NM's HP in the process. Miser Murphy cannot be bound easily. This can be a very hard fight.
Possible to solo as a 75 NIN/DNC by keeping your shadows up as much as possible; you may also bring a healer to be safe.
This fight was very easily soloed on 85SAM/NIN.
This fight stood no chance with a 90BST; subjob didn't matter.
Done without much trouble as a 61 SCH/RDM with 4 trusts. Used Accession to put Enfire on everyone and keep Blink on tank. He only got zapped about two or three times and Murphy burned down nice and quick. Scholar's Pants is helpful for the increased Enspell damage.