Mika Ryuugu left Ibaraki for Tokyo ever since her daughter Rena found her out. She lives with her daughter Ayano and husband Akihito, masking a facade of happiness. But deep down a mess of self hatred festers and she knows that she can't hide from Ayano or Rena anymore. What happens when Ayano says she wants an older sister? Will the two get along or be torn apart by old wounds?