When he was young, Rakker was not well accepted in the group of chimpanzees at the zoo where he lived and was repeatedly attacked by some members of the group, suffering serious injuries.

Still at the zoo, one of the chimpanzees who accepted Rakker was Simon (Sam), who became his faithful companion and went to the Sanctuary with him in 2004. Rakker is shy, introverted, and reserved. He still carries the trauma from his life at the zoo to this day and is very afraid of other chimpanzees. Despite this, he enjoys the company of people he trusts and shows himself to be very gentle and affectionate.