Gonji

 (ゴン爺) is Mukoda's 4th contracted familiar for 300 years, a 3024 years old male ancient dragon (エンシェントドラゴン).

History
The legendary monster at the top of the Dragon species, who is known to Fel as his enemy and rival way back 400 years ago. Then he went back and forth on another continent, and went into dungeon, King of Elman for 200 years, slept on the lowest layer, until Mukoda appeared. He confronted Mukoda who appeared to break through, but he was impressed by the taste of garlic steak made by the Mukoda and made a familiar contract. However, he had a 300-year temporary contract for some reasons and decides whether to continue in 300 years. Other than being quick, he has the strongest status in his work. Originally, a dragon with a huge black scale and as huge as a mountain, it has changed its size to that of Fel's size because of its food supply, and its capability has declined in purpose. His character is fickle and moves on his own pace, and in his subordinates he calls Mukoda "Nushi-dono or my Lord."