Джек Ракан

Jack Rakan (Jacobus Racan on his pactio card as the "k" in his family name is replaced with a "c" as is standard on all pactio cards), also known as "Rakan of the Thousand Swords", is the large, dark-skinned member of Nagi's group. He appears to be a powerful fighter, demonstrating incredibly destructive attacks with relative ease. His Pactio item is a blade that can transform into (in his words) "any shape imaginable" and can also take the form of a giant sword falling from the sky for an immensely powerful strike. He also demonstrated the ability to emit a high-powered laser from his body at a whim.

Rakan initially encounters Negi (in his older disguise) in the Magical World witnessing his battles in the tournaments to raise money to free some of his students. Seeing him without a special ultimate technique, he offers Negi to teach him one for a huge fee. However, after the two of them are attacked by a shadow-manipulator who wants revenge on Nagi, Rakan is forced to save Negi's life for free as well as decides to become his teacher without the fee. Rakan then teaches Negi a technique called Magia Erebea, a forbidden technique created by Evangeline A.K. McDowell. (Source: Wikipedia)