Klaus Heissler

Klaus Heissler is a fictional goldfish of the animated series "American Dad!". He was created by Seth MacFarlane. He is voiced by Dee Bradley Baker in a German accent. 
Klaus was once an East German Olympic ski-jumper until his mind was transferred into the body of a goldfish during the 1986 Winter Olympics by the CIA to prevent him from winning the gold medal, leaving him trapped in the goldfish's body. Ironically, Klaus started out on the series as a bully for his harsh criticism, but now he is the one being bullied by the family.