Pastel-kun is is originally the face of a crossover character from REFLEC BEAT, making his appearance in Pop'n Music: Usagi to Neko to Shounen no Yume. At first, he is a cameo for Hiumi's Win animation in Sunny Park and Lose animation in Lapistoria, and Parade form of Sanae-chan's brand new portrait (in this case, she receives a REFLEC BEAT song called Twinkle Wonderland).
Huh!? This is Pop'n?! Let's play with it because it's awe~some☆
Pastel-kun is a mouse with grey skin and black eyes. He wears a green striped, long-sleeved shirt, blue trousers and yellow shoes. He carries around a magic bubble wand and balloons.
Pastel's limelight appearance includes a lime green tank top with chartreuse, dark green, and yellow citrus patterns, along with normal aquamarine briefers. This outfit can be seen in Hiumi's Win animation and Sanae-chan's alternative portrait in Parade.
The only accessory Pastel wears is a cerulean snow cap on Hiumi's Lose animation in Pop'n Music Lapistoria.