|Saeki's sister ('Mom')|
|Age||Adult (likely lates 30's/40's)|
|Eyes||Unknown (possibly blue)|
Though her appearance is not clearly shown, she is seen wearing a purple dress or kimono, having long black hair, and her sprite owning brown eyes. She is the only character that isn't given a close up, and is only seen as a sprite.
Saeki was the younger of the two sisters. When they were young, their parents died, leaving Saeki's sister to raise her. However, she was unable to cope with this and Saeki ended up being placed in an orphanage and foster home. She still kept in contact with her elder sister, though their relationship remained strained. It is implied that Saeki's sister was jealous of her; she also developed severe hysteria at some point in her life - it likely stemmed from the trauma of losing her parents and having to be responsible for her little sister at such a young age. At some point during her life, Saeki's sister married or entered a relationship with an unnamed man and had a daughter named Miki. Due to her hysteria (and perhaps, her jealousy over her closeness to Saeki), she began verbally and emotionally abusing her daughter from an early age, though it was probably not intentional and she does appear to love Miki. It is unclear what happened to Miki's father, as he is never mentioned in the game. It is possible he died or left Saeki's sister, which would've contributed to her hysteria.
When Saeki told her sister that she was two months pregnant, she accused her of getting pregnant only to keep her husband happy; she also expressed jealousy towards Saeki due to her being able to marry a rich man, afterwards, she walked away. After Saeki suffered a stillbirth, and was abandoned by her husband, her sister provided no support to her, instead making fun of her, calling her crazy and ignoring her plight. She even forbade her daughter from visiting her aunt. After Saeki committed suicide, she still claimed that her sister does everything for attention and expressed little sympathy, though it is possible she acted this way to cover up her true emotions.
Saeki's sister calls Miki numerous times during the game to check up on her. In a phone call, when a distressed Miki requested to return home without explaining what had happened, she rejected her daughter's offer and forced her to stay, claiming that her aunt's home is her home now, and immediately hung up. Later on, Saeki's sister calls Miki again, asking what was the last call about; hearing Miki crying on the phone, she will ask if she is okay.
In the good ending, Miki begs to be allowed to come home, saying there is a monster. Saeki's sister will accuse her of having "all of these delusions" and calls her crazy, making fun of her and even telling her to hang herself like Saeki did. Later on, Miki discovers that her mother is saying those things because of her hysteria condition worsening, and decided to move back home with her to help her get better.
In the bad ending, Miki only said she was lonely and apologized for "saying such strange things"' Saeki' sister forgives her and asks her to call her if anything happens.
Saeki's sister appears to be caring at times but most of the time she is seen as a hardhearted and even cruel person. Due to suffering from hysteria, she is uncontrollable at certain times. To her sister and her daughter, she can reject their offers, abandon them, and bully them, even when it comes to life threatening situations, but she is not ashamed for doing so. It is obvious she is a mentally scarred, insecure and unhappy woman, who blames most of her problems on others. She expresses jealousy of her younger sister and claims she is attention-seeking. This is likely because Saeki got things she herself couldn't obtain; a wealthy husband and a loving replacement family (in the form of a foster family). She also appeared to be jealous of her daughter's close relationship with her sister and she seems to have abandonment issues. Although she can seem cold and hateful, Saeki's sister is just as much a victim of tragic circumstances and mental illness as her daughter and sister.
Saeki and her sister had a very strained relationship. Whilst Saeki was always kind and polite, her sister was often blunt, unsympathetic or downright cruel to Saeki. It is implied that Miki's mother was jealous of Saeki and took out her own feelings of unhappiness and insecurity on her sister. When Saeki committed suicide, her sister claimed she was just doing it for attention and didn't seem openly upset, but its possible this was just a cover for her true feelings. Whilst Miki's mother thought of Saeki as "crazy" and "attention-seeking", she never openly stated that she hated her and most of her horrible behavior towards Saeki seems to stem from her hysteria condition. Saeki also seems to imply they were closer as children, so there's a strong possibility that she did love her sister, in spite of her poor treatment of her.
Saeki's sister can be unkind and even abusive to her daughter Miki. They are not very close and Saeki often makes fun of Miki or puts her down, and is unsympathetic towards her problems. However, as with her younger sister, her abusive behavior towards Miki is apparently caused by her hysteria and mental instability, more so than genuine hatred of her daughter. Saeki's sister does seem to love Miki, as she expresses concern for her on a few occasions, calling her several times throughout the game to make sure she's alright, asking her if she's okay when she hears Miki crying and telling her to call her if she needs anything.