Leonard is a koala who shows to have a fear of Penguins. He appeared in "Night and Dazed", where Private tries to show Leonard that they will not hurt him. When he accidentally gets shot out of the zoo by Kowalski's new evacuation system, the Penguins set out to rescue him. Leonard refuses to be helped, but Skipper warns him about the dangers of the city (like dogs, cars and children) so Leonard agrees to be helped. Back at the Zoo, Leonard finds Marlene and is as scared of her as much as he is scared of Penguins.
In Kanga Management he is forced to share a habitat with Joey after the penguins blow up his habitat. Though things didn't work out, they both agreed that it was all the penguins' fault leading to a friendship where they realize that they have one thing in common.
in nighty night ninja he seems to have a kind of sleep acting like after seeing shirtless ninja action theater, he starts sleep fighting and after watching lunacorns he does sleep loving.
Leonard is incredibly paranoid, seemingly afraid of everything. He tends to be anti-social and nervous as well, which is probably because of the fact that he has a fear of everything (Panophobia or Pantophobia). Though he also has a brief issue with sleep fighting. Sometimes Leonard cannot help himself but point out the stupidity when facing an enemy.