Irewig has the appearance of a centipede with a dark blue chitin and a yellow underbelly. His face, four arms and legs are orange. Mr.Mad has glaring eyes with light-blue sclera and sharp teeth with two prominent red fangs. He has red antennae that are slightly crooked near the end and and an orange pincer with red tips on his tail. He also wears red socks and straw sandals.
Irewig has a fierce and wild personality, which he passes onto the victims he Inspirits.
Anyone Inspirited by this Yo-Kai becomes easily ticked off and prone to bursting into angry rants about even small, insignificant grievances. In the anime, Irewig does so by using the stinger on his tail to pinch his victims, making them angry.
Irewig can be found on Mt. Middleton in Present-day Harrisville. (Bony Spirits and Psychic Specters only).
In the Anime
Irewig debuts in EP073, having Inspirited Lily Adams and causing her to fly into a rage when Nate makes requests of her. After Nate identifies Irewig, his attempts to have Jibanyan and Happierre deal with Irewig backfire after they become Inspirited in turn. Nate eventually decides to summon Komasan, who ends up channeling his anger in cleaning chewing gum off the streets and building birdhouses, forcing the group to join in the latter activity, including Irewig. Exhausted from the ordeal, Irewig surrenders and gives Nate his Yo-Kai Medal.
Irewig is based on the mukade or oomukade, a youkai born from the Asian red-headed centipede. Aggressive and with a painful bite, much like the actual centipede, it only differs for its massive size. Its weakness is human saliva.
"Irewig" is a portmanteau of ire (anger) and earwig.
"Mukamukade" is a portmanteau of mukamuka (angry, ticked off) and mukade (centipede).
"Mosquereta" is a portmanteau of tijereta (earwig) and mosqueado (mottled)
"Scoltine" is a portmanteau of "scorpion" and "coltine" (put up with)