Reika Uehara Masayo lives peacefully with Yukio Mimura in their family mansion, sharing mutual feelings. Their existence is disrupted when their cousin, Hayato Mimura, arrives and demands they vacate the property. To resolve the dispute, Hayato proposes a contest mirroring a method used by their fathers: whoever succeeds in "breaking" Reika first wins ownership of the mansion. Reika is thus central to this contest. No further narrative or descriptive details about her background, personality, physical traits, relationships, development, or expanded role in other media are provided.