30 Lewd Days with My Adolescent Little Sister

30 Lewd Days with My Adolescent Little Sister is a 2D cohabitation simulator for players who want a slow-burn, domestic romance with a quiet, intimate tone. It plays out small and personal rather than dramatic.

Story

When their parents' circumstances force them to share a home for thirty days, a brother and his adolescent sister find themselves alone together for the first time in years. She keeps her distance at first, and their days together are awkward and cautious. Little by little, through daily conversation and small mischievous moments in private, the gap between them starts to close.

Gameplay

Each of the thirty days follows the same rhythm: the player spends time with his sister, choosing how to talk to her, tease her, or push a little further when the moment allows. Her reactions shift depending on how she's treated, gradually softening as familiarity builds. Progress is measured day by day, with the household routine itself forming the core loop.

Features

• Day-by-day structure that tracks a single relationship changing over a fixed span of time
• Animated 2D scenes depicting the couple's private moments
• Dialogue-driven interactions that shape how quickly the sister opens up