Markkio (マルッキオ, Marukkio) or "Banker" (銀行屋, Ginkōya), which is the name he goes by, is the person who supplies Huang, the Kou Empire's paper money, to Ahbmad Saluja, King of Balbadd. Banker and the Weapons/Arms Dealer who provided weapons/arms to the Fog Troupe are the same person.
Markkio was a Magician in Alma Torran, and was part of Solomon's resistance that sought to overthrow the orthodox government. He fell into despair after David Jehoahaz Abraham and the Elders killed his family. After Solomon stole and distributed Ill Ilah's Rukh, Markkio was disillusioned and joined Al-Thamen.
It is shown that Markkio might be still alive, but he has no memories of what happened in Balbadd, as he comes to greet Sinbad during Sinbad's stay in the Kou Empire. Sinbad comments that he was surprised that he was revived. He also notes that the person before him and Markkio he knew probably aren't the same person.
Banker has shown some ability to manipulate Black Rukh.
- Borg: This is said to be the proof of a Magician. It's a defensive ability. It blocks out attacks with evil intentions. It also blocks out all physical attacks and magical attacks to some degree. It's strength, however, depends on the person.
- The crown of thorns on his Keffiyeh headdress is a symbol of debt in Islamic mythology, which relates to his purpose when disguised as the Banker.
- In the manga, Markkio was defeated by Sinbad. In the anime, he was defeated by Ithnan. 
- Markkio's first appearance chronologically was at Sheba's side in Alma Torran.