|Allies||His group of friends|
|Enemies||The Three Investigators|
|First Appearance||The Secret of the Terror Castle.|
|Last Appearance||The Mystery of the Headless Horse.|
Right from when the sleuths started their firm, he had proved to be a hindrance for them. When Bob Andrews was searching information about the Terror Castle in the library, he had left one of the firm's business cards with "Terror Castle" written behind. Skinny saw this and quickly came to the Terror Castle to hinder their investigations.
Later in the books he even traps the three sleuths in a room and plots to steal a ranch from one of their friends named Diego Alvaro, and as punishment for being quite diabolical, he was sent to a military school by his father.