Who is Elektra and Iphigenia Binewski from Geek Love and what is their importance?

Elektra and Iphigenia Binewski are Siamese twins who possess an inherent talent on the piano. Their skill and unique appearance is the only tent act in the Fabulon that can compete with Arty's tent act. For this reason, Arty competes with his sisters throughout his life. The sisters have a fan base and many admiring followers, which prompts Arty to create not only followers, but a rabid cult.