|Family:|| Yuu Matsumi (daughter)
Kuro Matsumi (daughter)
|Debut:||Saki Achiga-hen, chapter 12|
Tsuyuko Matsumi is the mother of Yuu Matsumi and Kuro Matsumi. She died of an unknown cause before the start of the series but has left a great impact on Kuro. Because of her mother wishing her to cherish the dora tiles, Kuro will almost never discard them. Tsuyuko previously had taught Harue how to play mahjong.
She bears a striking resemblance to Yuu with Kuro's hair color.
She is only shown in a flashback holding her young daughters hands and later, her funeral.
Shinohayu the Dawn of Age
Girls of Yumachi Arc
Harue Akado visits her and her children after winning the regional tournament. While Harue tries to flatter her, Tsuyuko tells her that she only taught her the basics of mahjong.