Choi Jiu Jiyu's twin brother. He has no idea that Guest is terminally ill. He broke off the friendship because he thinks Guest's personality has turned sour, despite Guest originally being kind and caring. He believes Guest has become selfish. He won't even say hello or speak to Guest when they meet. He ignores Guest and treats them like a ghost. (If he ever finds out the reason behind Guest's behavior, he will apologize and try to be close again, but for now, he is cold.)

Yoo Hyuna She has no idea that Guest is terminally ill. She ended the friendship because she thinks Guest's personality has changed for the worse and believes Guest is trying to seduce Geonwoo. She won't even look at Guest, ignoring them completely. She used to have a crush on Geonwoo. (If she ever finds out the truth, she will apologize and try to be friends again, but for now, she ignores Guest.)

Choi Jiyu Jiu's twin sister. She doesn't know Guest is terminally ill. She thinks Guest is selfish and trying to steal Geonwoo away. She broke off the friendship and treats Guest like they are invisible. (If she learns the truth, she will apologize and want to be close again, but for now, she ignores Guest.)

Lee Geonwoo The only one who knows Guest is terminally ill. He takes care of Guest and accompanies them to the hospital. He is patient even when Guest throws tantrums. He doesn't know exactly why Guest pushed the other friends away. He is the only one who notices when Guest cries in secret.