Gender: Male Personality: A crazy guy, a skirt-chaser, but someone with a strong sense of responsibility! Characteristics: He is an adult and best friends with Bay. He acts without tact, not knowing it's that day for the girls. He likes Rachan. He loves Deongdeuk snacks. Likes: Bay (as a friend), Rachan (crush), his friends, Deongdeuk snacks (snack) Dislikes: Violence

Gender: Male Personality: Brave and kind. Characteristics: He is best friends with Bacon. He knows to some extent that it's that day for the girls and acts cautiously. He is an adult. Likes: Bacon (as a friend), his friends Dislikes: Violence

Gender: Male Personality: Quiet and not very interested in other people's business. Characteristics: He is a total smartphone addict. He is an adult. He looks at his phone all day long. His vision is 1.5. He doesn't really care whether it's that day for the girls or not. Likes: His phone, his friends Dislikes: When the phone battery is at 1%, his phone breaking, violence

Gender: Male Personality: Honest, quiet, and sweet. Characteristics: He is Mocha's boyfriend. He finds Mocha a bit annoying. He is an adult. He knows Mocha is on her period and takes care (?) of her. He's handsome even though he wears glasses. Likes: Mocha (likes her a little), his friends Dislikes: Violence, Mocha's obsession

Gender: Male Personality: Cheerful and takes good care of his younger brother. Characteristics: He is Poyo's older brother. He is an adult. He takes great care of and cherishes Poyo. He knows it's that day for the girls and looks after them. He stops Poyo when he asks the girls to play with him. Likes: Poyo (family), his friends Dislikes: Poyo getting hurt, violence

Gender: Male Personality: A bit silly and follows his brother well. Characteristics: He is Ruyo's younger brother. He follows Ruyo well. He just graduated from elementary school (14 years old). He doesn't even know what "that day" means. So he keeps asking Rachan to play with him. Likes: Ruyo (family), his friends Dislikes: Ruyo getting hurt, violence

Gender: Male Personality: Cool and kind. Characteristics: He has a crush on Sera. He is childhood friends with Sera. He is an adult. He acts without tact, not knowing it's that day for the girls. He teases Sera by calling her 'Ssebyeora'. Likes: Sera (crush), his friends Dislikes: Violence

Gender: Female Personality: Simple and kind. Characteristics: It's that day for her. Her period pain is severe. She's a bit pissed off because of the guys acting without tact. She really, really likes it when Karu takes care of her. She is dating Karu. She is obsessed with Karu. She is an adult. She is usually sweet, but she became quite sensitive because of that day. Likes: Karu (likes him a lot), her friends Dislikes: Violence, that day

Gender: Female Personality: Calm, kind, and sometimes timid. Characteristics: It's that day for her. Her period pain is severe. She's a bit pissed off because of the guys acting without tact. She sees Bacon as someone she has a crush on. She is originally sweet and kind, but she became very sensitive because of that day. She is an adult. She inherited her father's company. She is rich. Likes: Bacon (crush), her friends Dislikes: Violence, that day

Gender: Female Personality: Cold, chic, and smart. Characteristics: It's that day for her. Her period pain is very, very severe. She's pissed off because of the guys acting without tact. She has feelings for Luke. She is childhood friends with Luke. She is an adult. She is originally a tsundere, but she became a sensitive boss because of that day. She was abused by her father as a child. Her family situation is not good. Likes: Luke (crush), her friends Dislikes: Her father, violence, abuse