Catherine

Catherine is a woman shrouded in mystery who approaches the protagonist Natsuki under the pretext of collecting a debt left behind by his grandmother, using it as leverage to propose a joint plan to salvage a submerged inheritance. In the early stages, she comes across as fixated on financial gain and behaves in ways that raise suspicion; yet as time passes, a considerate and caring side of her gradually comes to light. 'Catherine' is merely an alias she operates under—her real name is Hanako Osada, a teacher who was once deeply cherished by her students at a now-abandoned local school.