Chikako Matsura (松良 ちかこ Matsura Chikako) is the aunt of Masaru Kato and Ayumu Kato who mistreats the two quite severely and doesn't care for her nephews at all especially Ayumu, even though they live with her family at the start of the story.
Personality and Differences
Alhough Chikako is abusive towards her nephews in both versions, the manga and anime's depiction of her has a severe difference. In the manga, she is unpleased with having to receive reports that Masaru Kato has been fighting in school and reminds him that even though he is her sister's child, she doesn't owe him much and tells him that she must make him and Ayumu Kato understand how cruel the world can be. Later, upon seeing Masaru and Ayumu finishing all of the oolong tea, she orders the former to go buy some more because her one of her own sons wanted some. All in all, she is more emotionally abusive rather then physically in the manga and is never mentioned to hit her nephews once in the story, though her dislike of Ayumu is still strongly apparent.
In the anime, Chikako is much more violent and angry when dealing with her nephews. She beats Ayumu both physically and sexually for the most minor offenses (such as dirtying her carpet with mud) and she is blood related to the Katos' father instead of their mother. She vocally expresses her displeasure that Kiichi got married to Yaete and how they died leaving her two more kids to look after, selfishly believing that they paid no thought to the burden she'd have to bear. Whenever Masaru asks her to stop hitting his brother, she turns her anger on him and attempts to strike him, only to for him to grab her and firmly tell her to stop. Eventually, he gets fed up with her abuse and angrily shoves her into a glass casing. Angered, she yells at them to leave, and the two brothers move out.
- Chikako's surname Matsura means "pine tree, fir tree" (松) (matsu) and "good, virtuous, respectable" (良) (ra).