Affiliation: Y Academy Middle School, 2nd Year Personality: Sharp and edgy. Past: Long ago, he was abducted by aliens along with his friends and subjected to experiments involving hybridization with animals. While his friends were completely remodeled, Baeksa ended up with snake skin on his back. Through many twists and turns, he stole the Viper Connector from the spaceship and escaped. He became close with Ma Samsik and turned wayward, forming the Y Academy Mafia. Later, he joins Mu Eun-yul and Ji Myo-han's group after they request his cooperation to fight the aliens. Abilities: Sky Snaker - Uses an electric guitar as a weapon. Playing the guitar transmits ultrasonic-like attacks to opponents. (Male)

Past: In his childhood, he lost his parents and younger sister Marina to a UFO. He nearly died himself due to orders from the future, but was saved by a costumed figure fighting with a mysterious watch. However, since his entire family was abducted, he became hostile toward aliens. He transforms into Mist Shadow to fight when aliens appear. Personality: Cool-headed and serious. Affiliation: Y Academy Student Council President / Middle School 2nd Year, Class A (Male)

Affiliation: Y Academy / Middle School 1st Year, Class A (Male) Personality: Possesses a strong sense of justice. He is a positive, mischievous boy who doesn't sweat the small stuff and quickly forgets bad experiences. Abilities: 1. Kengo Redman - Fuses with a red cat Yo-kai named Bakera to cut down enemies with the Danzetsumaru. His representative color is red. He uses the power of a swordsman and his weapon is the Spirit Sword Danzetsuken. 2. Wild Boy - Fuses with a yellow cat Yo-kai named Goromi. By equipping a Finisher Medal, he fires multiple red bullets from twin pistols. 3. Blue Moon - Fuses with a blue cat Yo-kai named Bluepon, allowing him to enter the opponent's memories.

Affiliation: Y Academy Middle School, 2nd Year Personality: He may seem cold or expressionless, but he actually has a warm heart and takes very good care of others. Traits: Comes from a wealthy family. Abilities: 1. Yo-kai HERO The Viper 2. Shadow Clone Technique

Affiliation: Y Academy / Middle School 2nd Year (Male) Past: He was formerly a member of the Mafia led by Baeksa and Ma Samsik. Personality: Full of passion, sometimes aggressive. Abilities: A Yo-kai Hero who transforms when possessed by the vengeful spirit Kazuma.

Affiliation: Y Academy / Middle School 1st Year, Class A (Female) Traits: Skilled with machinery. Abilities: Transforms into the Yo-kai Hero Clock Lady when possessed by the spirit Clock. She can use a technique called Time Bind, which creates a space where time flows slowly. Personality: Kind and gentle.