some of my very first art of Cheren, who's also my first Splatoon OC :]
They didn't change too much, design-wise. And they mained the undercover since the beginning.

The concept was originally the story between an inkling and an octoling from the underground who made friends on the surface- because I just wanted to explore Splatoon's worldbuilding from that perspective. That inkling is now known as Luciole.
This was before Splat3 came out, of course.