Shiko Academy student Ritsuka Tachibana is summoned by the boys of the Student Council and accused of violating school rules; a horrible incident happens at home.

Ritsuka meets the rest of the student council before leaving with Rem, its president, to pursue a promising lead in the search for her mother.

Ritsuka learns some truths about her family and the student council before having a confrontation with someone who isn't who he seems to be.