The Great Fitzphie Ooze Fest, as dubbed by Keefe, was an event that occurred twice, in which the combination of the salve applied to Sophie and Fitz's wounds, and the byproduct of the marrow regenerator they took to speed up bone recovery was incredibly oozy and smelly.
According to Sophie, it was a reddish-bluish-black color, and its odor resembled “weaponized morning breath.”