Komasan is a Komainu (though more closely resembling a shiba inu) with long, blue fiery eyebrows that look similar to Hitodama flames. He has ivory-colored fur with a light blue stomach, tail, and inner ears. His eyes are a lime green color and he has red swirls on his cheeks and hips. He carries a green furoshiki (wrapping cloth used to store and carry items) with a white spiral pattern wrapped around his shoulders. It is seen that in EP049 when Komasan and Komajiro are Santa's helpers, at the end Komajiro gives him a green sling pouch so he could store extra things which Komasan now wears in the anime, Yo-kai Watch 2, the games after Yo-kai Watch 2, and Yo-kai Watch: Wibble Wobble. This appearance is somewhat retained in his human disguise.
Komasan is an ice cream-loving Yo-kai from the countryside. After his shrine was demolished, he wandered into the city in search of soft serve ice cream.
In the anime, Komasan is portrayed as a "country bumpkin", unaware of the goings-on of city life. He uses the -zura sentence ending, which is how people from rural Nagano Prefecture (particularly Suwa) speak and is typically used to satirize country folk. He exclaims "Monge~!" whenever he is surprised or impressed ("Oh my swirls!" in the English dub).
He tries his best to learn as much as he can to present himself as a good role model to his younger brother, Komajiro. He pretends to be very knowledgeable about city life. However, Komajiro has a high capacity to adapt to the city and soon becomes a DJ at a nightclub. Komasan spends most of his time roaming the city in search of delicious food, particularly soft serve ice cream, as well as going on adventures with his brother.
Komasan is sometimes uninterested in changing people's minds. In one of his side stories, 'Movin' On Up', when the president of the company Komasan was working at retired, he says "Well, that's a plum great idea, y'all.".
Poofessor showed up in an episode and he shared some interesting facts with Komasan, but Komasan was more interested in enjoying nature, (he was catching butterflies at that moment) finding four leaf clovers, and sleeping.
When Nate summoned Komasan to stop Irewig, he ended up getting inspirited by the centipede Yo-kai, however, the way he channels his anger drove him to work toward stopping whatever problem would tick him off (e.g, scraping all the gum off the street), to the point where he eventually forced Nate, Whisper, Jibanyan, and even Irewig to help him.
Whenever he serves as a judge in a contest, he has a strange way of deciding who wins. For example, in the Yo-kai Red & White Song Battle, Komasan chose the Red team as the winner because Jibanyan was red and happy while Whisper was white and unhappy.
In the game and movie, Komasan's power (and soultimate) is the Spirit Dance. He also has quite a high spirit stat (for a rank D Yo-Kai).
"Komasan" is the "koma" half of komainu followed by the -san honorific.
Komasan is based on a komainu, a guardian statue halfway between lion and dog. Originating from Chinese guardian lions, they guard the entrance or inner building of Shintoist shrines. They usually come in male-female pairs, placed at each side of the entrance. Because of the Buddhist influences, the left one's mouth is always open while the right one's closed, pronouncing "a" and "um", which are the first and last letter of the Sanskrit alphabet: together they form the sacred syllable Aum. Incidentally, these letters are the original names of Komasan and Komajiro's Alpha and Omega skills.
He is voiced by Melissa Hutchison.
Despite being described as a countryside person, in the Portuguese dub he speaks with a Porto accent, despite Porto being one of the most urbanizated portuguese districts.
While he is based primarily on a Komainu, Komasan's leaf transformation and love of food are traits often attributed to Tanukis.