ふたりのポラリス

Hikari Amamiya, a sharp and socially adept high school girl, navigates life with confidence until her mother’s remarriage brings her a new stepsister, Mizuki Suzumura. Mizuki, timid and often overlooked, struggles to find her place in their shared class and new family dynamic. Together, they confront challenges at school and home, from shifting friendships to tense family moments, gradually reshaping their relationship. A nearby sibling duo, bound by blood, adds new layers to their evolving circle, stirring both rivalry and support. (Unreviewed summary by Grok 3)