Thirty Days with My First Love Sister is an indie romance simulation game that blends RPG-style stat management with a fully video-based interactive story. Players step into the role of a young man whose childhood friend and promised elder sister returns from abroad to stay for thirty days before the new semester. The experience centers on daily choices that shape affection, daily life, and long-term outcomes in a pure, wholesome narrative.
Gameplay
The core loop revolves around a thirty-day calendar where daytime decisions guide the story across ten main locations and more than thirty sub-locations. Each destination offers sequences of AI-generated video scenes that advance the relationship through everyday activities and shared moments. Stats such as money, affection, stamina, and intellect shift based on selections, influencing available options and the overall path. Evenings focus on home interactions that include conversations, shared activities, and gradually deepening closeness as affection rises. Costume purchases unlock additional scenes, while a system of one-time key moments ensures certain milestones occur only once per playthrough. An anti-repeat mechanism draws events from a pool to maintain variety across multiple runs, and progress carries over with bonuses for subsequent attempts.
Game Modes
The game operates as a single-player simulation with branching narrative paths determined by cumulative choices over the thirty days. Four primary endings emerge from the interplay of stats and decisions: friend, lover, marriage, and a hidden secret branch. Cross-scene story arcs allow sequences such as visiting a bridal shop, riding a Ferris wheel, purchasing a ring, and reaching a proposal. The structure encourages repeated playthroughs to explore different affection levels and unlock exclusive content through inheritance mechanics that provide starting advantages on later runs.
Story and Characters
The central character is the non-blood-related childhood sweetheart who returns as a gentle, clever companion skilled in daily life and cooking. Her personality combines familiar sisterly warmth with the excitement of budding romance. All interactions remain wholesome, with no violence or explicit elements, and every character is established as an adult. The narrative emphasizes heartfelt daily moments and the gradual development of pure affection through consistent player choices.
Features and Systems
Over one hundred AI-generated video clips form the visual backbone, creating continuous scenes rather than static images. A real-time stat system tracks four core attributes that respond to every action. Costume unlocks expand scene variety, while Steam Cloud support preserves progress across devices. The production comes from a small indie team that combines AI tools with hand-crafted design to deliver a focused romance experience.
Is It Worth Playing?
This title suits players seeking a relaxing, choice-driven romance simulation with video storytelling and multiple endings. The emphasis on daily life choices, stat management, and wholesome relationship building provides a clear structure for those who enjoy narrative-driven indie games. Availability on PC through standard digital platforms makes it accessible for single-player exploration. The pure romance focus and lack of mature content position it for audiences interested in light, heartfelt stories rather than action or competitive elements. Multiple playthroughs reveal additional branches and content, supporting replay value for those drawn to affection systems and branching outcomes.
