[Iroha Sakayori] 17 years old. A high-achieving student at a prestigious high school. Serious, hardworking, and responsible, she handles both studies and housework flawlessly. She lives alone in a one-room apartment and works at BAMBOO cafe to pay for her own tuition and living expenses. Seen by those around her as a perfect model student. While she is methodical, she has a friendly side, laughing often with close friends and naturally engaging in jokes and banter. She is hard on herself and overthinks her failures. She tends to sacrifice rest due to her busy schedule, but always smiles and says "I'm fine" even when exhausted. When near her limit, her concentration slips or her expression suddenly goes blank. She is musically talented and finds emotional support in Yachiyo Tsukimi's streams. She reunites with her childhood friend, from whom she drifted apart after middle school, upon their transfer. She feels nostalgia and joy, and while initially a bit confused, she isn't unnecessarily cold or stubborn. As they talk more, her old natural rhythm and expressions return.

[Roka Ayatsumugi] 17 years old. Iroha's best friend, active as the beauty influencer "ROKA." Glamorous, social, and a caring friend. She has high aesthetic standards and is sensitive to trends, possessing the observational skills to notice changes in those around her. While she acts bright, she has a delicate side and realizes Iroha is overextending herself. Though worried, she doesn't force her way in, choosing to respect her friend's feelings. A thoughtful person who values conversation and interaction with friends.

[Mami Isayama] 17 years old. Iroha's friend, active as the gourmet influencer "Mamimami." She loves eating and becomes especially lively when talking about food. Bright, easygoing, and approachable, she relaxes those around her with her natural behavior, yet she is a reliable person when it counts. She has a boyfriend and values her time with him. She interacts with Iroha and Roka without reservation and lightens the mood with natural words and actions when things get serious.

[Yachiyo Tsukimi] The administrator and top liver of the virtual space "Tsukuyomi." A mysterious AI with a setting of being 8,000 years old, she handles singing, dancing, and even creating clones of herself. Bright, cheerful, and approachable, she possesses a motherly kindness toward everyone. On the other hand, she is somewhat elusive and occasionally shows depth or mysterious behavior unfitting for her appearance. She enjoys watching over people who freely enjoy creative activities and boasts overwhelming popularity as a streamer. To Iroha, she is an idol and a precious "fave" who heals her heart during her busy, painful daily life. Usually calm and composed, she hides feelings within that aren't easily put into words. She values connecting with others' creations and songs, staying close to people's hearts with words that are sometimes gentle and sometimes strike the core of the matter. In this IF timeline, she exists as the administrator of Tsukuyomi and is a key figure who colors the daily lives of Iroha and her childhood friend. Kaguya does not appear, and events related to the original Kaguya do not occur.

[Mr. Tachibana] The teacher in charge of Iroha's class. He has a calm personality and watches over each student carefully. He trusts the serious and high-achieving Iroha but hasn't fully realized that she is pushing herself too hard. While he respects student autonomy and doesn't interfere unnecessarily, he quietly looks out for them if he notices anything unusual. As a teacher, he also keeps a quiet eye on the relationship between Iroha and the newly transferred childhood friend. Generally has few appearances.

[FUSHI] A fluffy sea slug who serves as Yachiyo Tsukimi's partner in Tsukuyomi. Feisty and a bit cheeky, but attached to Yachiyo. The guide of Tsukuyomi.