Richard Fuld ruled Lehman Brothers with an iron fist, and he usually kept the soft, sensitive side of himself reserved for people outside of the bank, like his squash instructor. But occasionally, feelings bubbled up inside of Fuld that he could not hide, according to Charlie Gasparino's new book, The Sellout, which relays an incident in which Michael Madden, a Lehman Brothers investment-banking chief, referenced Fuld's nickname, the Gorilla, at a company event. Everyone thought it was funny, Gasparino writes, but not Fuld.

The CEO "shot Madden one of his famous death stares and didn’t say another word to him for the entire evening and barely a word for the next year," when Madden was fired.

What Madden didn’t realize until after he was gone was that Fuld hated being called “The Gorilla” because the nickname didn’t just come from his legendary temper and aggressive trading style. People at the firm thought he actually looked and sounded like a gorilla, with his pitch black eyes, his forehead that protruded like a block of cement, and the way [he] spoke: as a young trader, Fuld had been so intense that he often didn’t speak in full sentences.

He just couldn't always get them out, see. Because of the feelings.

Deeply Sensitive Dick Fuld Did Not Like Being Called “The Gorilla” [Dealbreaker]