Filo/Chronology

Volume 2
Originally, Filo had the appearance of a small pink Filolial chick (much like an actual chick) and would sit on top of Naofumi's head when they were on the road. However Filo grew very rapidly and within a few days was the size of a normal Filolial making such actions impossible but allowing her to grow to a size so that she could be used to pull their cart, this was thanks to Naofumi's monster tamer shield, which he unlocked from some egg shell's his shield had absorbed.

Filo also has exceptionally fast legs, so much so in fact that she was able to beat a dragon in a foot race, despite many unfair attempts to make her lose. Filo's growth, however, was not finished at that point as a day later she had grown to exceed the size of a normal Filolial and upon interrogating Beloukas, he found that she was or maybe a "Filolial Queen." Naofumi, wanting to know more about what a Filolial Queen was, offered to have the slave trader take care of Filo for a few days, but, shortly after leaving her, he was called back due to a ruckus she had caused after being separated from her master. After Naofumi and Beloukas got into an argument, a strange voice was heard from the cage Filo was in, and much to everyone's surprise, Filo transformed herself into a small human girl with blonde hair and reached out for Naofumi.

Volume 3-13
(information to be added later)