✅ Strongly recommended for players who want a game where you play as a female agent investigating a school outbreak, where failure leads to routes where more characters fall under enemy control.

You play as Akesuzu Beni, investigating incidents caused by “Poison” entities spreading across the academy. With multiple suspects, your goal is to find the culprit before things get out of control. Investigate, identify, and confront. Win to progress. Lose and the story continues as Beni and others fall under enemy control.

Female Protagonist — Akesuzu Beni (朱雀 紅) / Agent Sirius

Adventure / Exploration AVG / Light Action / Adult (R18) / Corruption / Pleasure Fall / Mind Control / Brainwashing / Academy / Transforming Heroine / Chain Corruption / Harem / Group / Yuri

■ Core Themes
● Pleasure Corruption（快楽堕ち） ● Corruption / Fall（悪堕ち） ● Chain Corruption（連鎖堕ち） ● Mind Control / Brainwashing（精神支配 / 洗脳） ● Academy Invasion（学園侵食） ● Transforming Heroine（変身ヒロイン） ● Cult Indoctrination（変態宗教）

■ Sexual Content
● Full Nudity（全裸） ● Oral（口） ● Vaginal（膣） ● Anal（肛） ● Threesome（3P）
● Foursome（4P） ● Group Sex（乱交） ● Lesbian（レズ） ● Creampie（中出し）
● Masturbation（オナニー） ● Ahegao（アヘ顔） ● Dirty Talk（淫語） ● Squirting（潮吹き） ● Groping（痴漢） ● Doggy Style（バック） ● Watersports（放尿）

■ Fetishes & Extras
● Big Breasts（巨乳） ● Small Breasts（貧乳） ● Petite（小柄） ● Chubby（ぽっちゃり） ● Tanned（褐色） ● Gyaru（ギャル） ● Virgin（処女） ● Pregnancy（妊娠）
● Strap-on（ストラップオン） ● Sex Toys（アダルトグッズ） ● Nipple Piercing（乳首ピアス） ● Body Writing（身体落書き） ● Mask（マスク） ● Outfit Variations（衣装差分） ● Blindfold Play（目隠し） ● Confined / Ritual Situations（拘束・儀式） ● Exhibitionism（露出） ● Yuri Corruption（百合堕ち） ● Harem（ハーレム） ● Ugly Bastard（NTRおじさん系） ● Large Penis（巨根） ● Transformation Costumes（目隠し奴隷・青肌ニュル・褐色ギャル・王国国民・フリーダムスーツ） ● Post-Fall Playable Routes（堕ち後操作可能）

※ Note: Focus on gradual academy takeover, progressive character fall, and extended bad-end routes where the player actively participates in spreading the corruption rather than stopping it.

None; external patch required to access full adult content.

~4–6 hours for main story and bad endings; ~8+ hours for full completion, including collectibles, sub-events, and Dark Side routes.

None. Exploration is supported by NPC hints, while boss encounters are simple avoidance-based mini-games that become highly forgiving after the first failure (unlimited mode).

High-quality artwork by さなつき, with appealing heroines, extensive character portraits across a large cast, and multiple visual variations tied to each corruption pattern.

Atmospheric BGM included. Sound effects enhance erotic scenes; no full voice acting.

Chapter progression includes victory and defeat outcomes unlocking different scenes, a separate Dark Side route triggered by a key choice, extended post-defeat sequences where you control corrupted heroines to convert others, and expanded collectibles (Fallen Pedia, monster encyclopedia, sub-events).

An uneasy atmosphere spreads across Star Haven High School as a series of strange incidents begin targeting female students. Rumors quickly escalate into something closer to urban legends, and as head of the detective club, Beni Akesuzu takes it upon herself to uncover the truth.

Behind the scenes, Beni is also an agent of Bancho, a secret organization that deals with supernatural threats. They already know what is happening. Creatures known as “Poison” are manipulating desire and slowly trying to take control of the school.

With a list of suspects that includes both students and teachers, Beni and her partner Nadeshiko begin their investigation. Their goal is clear. Identify the culprits and stop the spread before the entire academy falls under their influence.

① Exploration & Investigation
Move through the school, talk to students and staff, and gather information to identify the culprit among several suspects. Certain characters provide hints to guide progression.

② Corruption System
Beni has enhanced abilities but high sensitivity to stimulation. Witnessing events increases her corruption level, which can trigger scenes and affect progression at higher levels.

③ Avoidance Action Encounters
Once the culprit is identified, the game shifts to simple dodge-based action sequences. The objective is to avoid obstacles and reach the goal. Difficulty is low and does not block progression.

④ Failure & Alternate Routes
Defeat does not result in a game over. It unlocks alternate routes where Beni falls under enemy influence, continuing the story with different outcomes and character states.

⑤ Collectibles & Progression
Exploration unlocks entries such as character profiles, enemy records, and world information, providing additional context and tracking progression.

Agent Sirius is easy to get into, with a simple loop of exploring the school, identifying the culprit, and moving into boss fights. I liked how straightforward the progression is, and the “Pleasure Corruption” system adds a clear sense of escalation as Kurenai gradually loses control.

The content also stands out, with solid variety in outcomes, post-corruption scenes, and character states, especially if you enjoy defeat-based scenarios and transformation themes.

That said, the gameplay itself stays pretty basic. The investigation phase is limited, and the dodge-based combat feels more like a setup for H-scenes than a real challenge. The early game can also feel a bit overloaded with characters and information.

If you’re here for corruption and bad ends, it delivers consistently, with the gameplay and story mainly there to support that experience rather than take the lead.

▲ Strong chain-corruption routes, including playable fallen heroines
▲ Multiple transformation patterns with distinct art and dialogue
▲ Added collectibles and optional sub-events
▲ Smooth exploration with simple, forgiving action segments
▲ High-quality さなつき artwork with many fallen-state variations
▲ Additional patch unlocks full adult content
▲ Fully built around corruption and bad-end progression

▼ No full voice acting
▼ Exploration can feel repetitive on repeat playthroughs
▼ Limited appeal outside its niche