Custom Skater is Kevin's character from the video Tony Hawk Proskater 4 has aged like a fine milk.
Look[]
Custom Skater is a baby. Indeed, he's 1 year old, but "is like ten foot tall" and has a neckbeard and a bowl cut. Also, as usual in Kevin's characters, basically every cursor regulating his features are pushed to the max: Custom has the maximum height possible in the game, and the biggest feet or arms.