Jiemma (ジエンマ) is the Guild Master of the currently "strongest" Guild in Fiore, Sabertooth. Jiemma is very strict in his beliefs. He firmly believes that Sabertooth is the strongest guild in Fiore and wishes it to remain that way.
When Yukino Aguria lost a match in the Grand Magic Games, he forced her to strip down in public, remove her guild mark, and leave the guild. He also does not seem to care much for his subordinates that fail to meet his expectations as he constantly called Yukino "trash" after she lost her match. ~!Even Sting and Rogue, despite their fame, power, and numerous victories prior, were "trash" in Jiemma's eyes and were ordered to erase their Guild Marks after their single-handed defeat by Natsu.!~