Another Sgt. Frog fanart, inspired by the Setsubun episode. They had this device that turned others into oni (demons) - which more or less involved simply being dressed in a bikini/loincloth and having horns. Keroro zapped Natsumi with it thinking he could defeat her with soy beans (since they're thrown at demons to ward them off), but didn't anticipate that she would be in control of demony powers as a result. XD

Made as a wallpaper for my old computer, so the dimensions are a lot smaller.