Komasan is a Komainu, more closely resembling a shiba inu with long, blue fiery eyebrows that look similar to Hitodama flames. Throughout his body and head, 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 (a cloth that can be wrapped, which is used for storing and carrying items) with a white spiral pattern wrapped around his shoulders. In The Koma-Santa Clause, he was given a green sling pouch from Komajiro after he helped deliver the presents for Christmas and uses it for storing extra things. That would become his later appearance, which is also seen in Yo-kai Watch 2 and Yo-kai Watch: Wibble Wobble. This appearance is somewhat retained in his human disguise.
Komasan is a Yo-kai that has a liking for ice cream, who comes from the countryside. After his shrine was demolished, he wandered into the city in search of better soft-serve ice cream.
In the anime and some other adaptations, Komasan is portrayed as a "country bumpkin". He usually speaks with a Suther accent, and is unaware of what goes on in the city. Whenever he gets exclaimed, he usually says "Oh my swirls!" (Monge~! In the Japanese version).
In the original adaptation, he usually ends his sentences with -zura, which is how people from rural Nagano Prefecture (particularly Suwa) speak and is typically used to satirize country folk.
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 Komasan: '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 Nathan Adams summoned Komasan to stop Irewig in Yo-kai 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 games 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 Buddhist influences, the right one's mouth is always open while the left one's closed, pronouncing "a" and "um", 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.