Unfortunately Solomon's description didn't provide enough information for Bakura to decipher what creature it was, and that was even assuming it was one that Pegasus had transformed into a modern day card. It was also entirely possible that it wasn't a monster he'd be familiar with at all, given that the necromancer wasn't from the same world.

"It's part of you. It could be like your given name, there but for all intents, inert. It won't hurt or take away from you. But if you choose to make it stronger... it's more like your true name. Capable of being a great force, but intertwined with who you are. It's not something you can stop, if you go down that path."