Icha Ane!

His father's sudden remarriage doesn't just give him a new stepmother, it hands him four older sisters at once: two by blood, two by marriage, and one of the new arrivals turns out to be the senpai he used to crush on in high school, whose older sister he already has history with. The world, as he keeps muttering, is uncomfortably small.

Living under one roof turns the whole household into a slow-motion collision of old feelings and new obligations. What starts as an awkward family reshuffle spends the rest of the summer becoming something much less family-appropriate, as four women who technically share his house also share none of his restraint.

You move through this as a visual novel, reading the daily grind of shared meals, shared space, and shared tension between the protagonist and his sisters, with choices steering things toward one of several possible endings. There's no combat, no stats to grind, just the slow unraveling of a household that was never built to hold this many secrets.