Super Sonico is a fictional character created to be the mascot of Nitroplus, as you can see in this Kawaii Super Sonico Cosplay Pictures, Sonico is identical with her cute-Moe face, her signature headphones, kawaii pink hair and Large Bust, I think Yonor (the Cosplayer) keep everything in touch in this Kawaii Super Sonico Cosplay picture.
If you run out of space to store your stationery, Sonico has a pen case that looks nice, warm, soft and convenient to store yours pens, I mean look at the first Super Sonico Cosplay Picture, I don't know how Yonor could be that creative (no bags anything can be a pencase). now I'm really jealous with that pen ಠ_ಠ.