Cosplay can go well beyond simple fandom; it's an entire industry of its own. People make it their job to play different characters, create costumes, and bring them to life. From the sewing machine to foam models to 3D printing, there are many who create things from scratch and take months and months to perfect their look. I see themes at different times to where certain characters that you might not see too often are all of a sudden everywhere because people have taken on the challenge of it. I used to see a few of the more famous accounts on Instagram and Facebook of cosplayers, typically people who've gained large followings and who end up being featured as guests at different events. Now it has exploded into something that is year-round, and there are even charity groups focused on cosplay.
