Admiral Ysionris Jeromi was the Chief medical officer of the UNSC Research station Hopeful in 2525.
He was a personal friend to Dr. Catherine Halsey, and performed a number of expirements on Binobo chimpanzees for Dr. Halsey. She was his star pupil, and he had never approved of her working with the Office of Naval Intelligence. He was a mentor to her and his dissaproval made her decisions more difficult.[1] The experiments he conducted were later used on the Spartan soldiers. However, he was not made aware of this and likely would have objected if he had known.
Sources
- ^ Halo: The Fall of Reach, pages 56/57