Isak
Isak was a chimpanzee who Lukas had fallen in love with. Ten years prior to Lukas beginning his employment there, he had been introduced to the zoo. The Kristiansand Zoo offered to take Isak in after poachers brutally killed his parents.
Isak would have been intimidated by the others because most zoos in Africa already house a large number of chimpanzees. But he was the sole one of his kind in Norway. But sooner or later, Lukas would find out that Isak was hiding something really bad.