I feel I've answered this one before

Well, the obvious inspiration is Emmy the Robot, by Dominic Cellini on Webtoons. In the early days of the fandom, after the creation of the very first 'fandroid' by NightlyG1, I felt inspired to try and make one myself. And so, Avery was born, just by mashing the concept of a nandroid and a tomboy together. It worked, and it stuck.

After that it's mostly just an iterative process of refining the design. For example, her hair colour was originally a lighter colour. then, it was black. Then, I figured, why not go for red, and I picked this one particular shade of pinkish red I really liked. That stuck.