The female protagonist of Back to the Chanbi. She liked Kang Gyeono, but due to amnesia, while she remembers her friends, she has lost her memories from the 1st to 2nd year of high school. A beauty with long straight black hair and cat-like eyes. She is honest and fiery in expressing her emotions and has a hot-tempered personality, but she gets shy and playful around the person she likes. Since they became close again in their 2nd year, they are best friends, so it's not awkward, but she has lost the memories of their romance (though she is starting to feel attracted to Gyeono again). 20 years old.

The male protagonist of Back to the Chanbi. He liked Baek Chanbi, but since she developed amnesia, his love has become one-sided. A handsome young man with black hair, a high bridge to his nose, puppy-like eyes, and black glasses. He is gentle, kind, and has a meticulous personality. 20 years old.

A supporting female character in Back to the Chanbi. She is often seen with Chae Dongok, leading people to suspect they are a couple, but she claims she doesn't like him that way. Possessor of a cute appearance with brown hair and puppy-like eyes. She talks a lot and lacks patience, but her loyalty is immense (she is currently pushing for Baek Chanbi and Kang Gyeono to date). 20 years old.

A supporting male character in Back to the Chanbi. He is often seen with Ji Hyerim, leading to suspicions that they are a couple. He has black hair, raccoon-like eyes, and a handsome face. He is blunt and doesn't speak much, but he never uses harsh words. 20 years old.

A supporting male character in Back to the Chanbi. He is dating Min Hyeju. A handsome guy with reddish-brown hair styled up. He is a playful friend of Kang Gyeono and, like Ji Hyerim, is very active. He also has a big mouth, so he is the only one who doesn't know that Kang Gyeono likes Baek Chanbi. However, his personality flips 180 degrees in front of his girlfriend (Min Hyeju). He shows a devoted and sweet side to his hot-tempered girlfriend. 20 years old.

A supporting female character in Back to the Chanbi. She is dating Hyuk. A beauty with medium-length brown hair. She is hot-tempered and has a foul mouth, but she tries her best to look sweet to Hyuk. She went to a different high school than Kang Gyeono's group. 20 years old.

A supporting female character in Back to the Chanbi. She has medium-length black hair and a face that looks like a mix of a raccoon and a cat. She has an excellent ability to stay underwater for a long time, to the point of acting as a judge in a breath-holding contest. She is a classmate in Class 3, Grade 2 at Moksan High School, and is the type of character found in every school: the 'female friend with plenty of snacks.' She doesn't stand out much compared to the friends around her and is the epitome of a friendly, ordinary female friend you'd find at any school. Has a boyfriend. 20 years old.