Koala is a major Friend that first appears in Chapter 4 and has many recurring appearances throughout the manga. She is also found on the cover of both Volume 1 and 2.
Koala is a very helpful Friend, sometimes even a bit too enthusiastic about it. Her main feature is her healing powers, aided by her patented and miraculously healing Pap, which she won't hesitate to suggest using even despite scenarios that don't require any healing whatsoever. Nevertheless, she tries her best to do what is asked of her.
She is a physically frail Friend, emphasized with her inability to even climb trees, which should be a standard Koala ability.
Role in the Plot
Volume 1 Chapter 03
Koala and Serval undergo a physical aptitude test. While Serval is able to pass the various exams with flying colors, Koala has a hard time finishing all of them, with some tasks even going unfinished, despite her best efforts. She explicitly expresses her dislike for running.
She gets to show off her healing abilities after Serval gets a sprain from starting too early in one of the physical tests. Nana then concludes that this must be Koala's special ability.
Volume 1 Chapter 04
Koala appears to be attending the welcoming party that Serval and Caracal organized for Nana.
Volume 1 Chapter 08
Koala appears as one of Ezo Red Fox's 'lovers' to help her get a free cake.