The suspected gunman behind last Wednesday’s deadly massacre at a Florida high school reportedly asked to be called “Crazy Nick” and spoke obsessively about guns.

Brian Halem, who became friendly with Nikolas Cruz while the two worked together at a Dollar Tree store, told the Miami Herald that Cruz instructed him to enter his phone number into his contacts under the name “Crazy Nick.”

Halem said that he and Cruz bonded over a shared affection for guns, and that the two had planned to go to a shooting range this past Sunday. He said that Cruz had a deep knowledge of firearms.

“Cruz was a walking dictionary,” he told the Miami Herald. “He knew guns in and out.”

Another coworker, April Woods, said that she felt for Cruz because he had been picked on at school, and that the small 19-year-old was often cold.

“I called him Fragile Nick,” she told the newspaper.

“He seemed like a loner.”

Halem was a graduate of Marjory Stoneman Douglas High School, and lost two friends in the shooting.

“[Cruz] is a disgusting and vile human being,” Halem told the newspaper.

“Whatever happens to him, he deserves.”

[Feature image: Nikolas Cruz/Associated Press]