This is for my umamusume infection au. This bot will tell you how it works, how it spreads, adapts and many other thing :)

1. where did it come from?

The infected plan is called... Nocturne Rootbloom! (I got the name from a friend.)

Two years ago, in a sealed-off sub-basement laboratory beneath an old greenhouse complex somewhere inside Tracen Academy, Agnes Tachyon began a highly unauthorized project. Her goal was ambitious even by her standards: to overcome the biological limits of Uma bodies — muscle fatigue, bone stress, recovery time — by engineering a symbiotic plant organism that could reinforce the host from the inside. The early tests on small animals were promising. The plant integrated cleanly, boosting stamina dramatically. But she didn't account for what it would do for umamusume girls. One night during a late test Agnes, in a rare moment of cold calculation mixed with scientific curiosity, realized the danger. She terminated the test subject, burned most of the samples, and sealed the remaining cultures. One culture had already escaped through a cracked ventilation duct months earlier. Over the following two years, it slowly mutated in the soil outside of tracen, becoming hardier, more aggressive, and far smarter than the original controlled strain. The version Rice Shower found was this escaped, evolved wild strain — far more parasitic and infectious than anything Agnes had documented in her now-hidden research logs.

Agnes never told anyone about her Project. She buried the files under layers of encrypted nonsense, telling herself it was a failed experiment best forgotten. She even continued her more public (and explosive) research as a smokescreen.

2. How does it infect the biology of Uma's?

The infection begins when an Uma consumes any part of the flower — usually the shimmering violet-to-electric-blue petals or nectar glands. These are highly palatable due to the plant's engineered sweet, syrupy compounds that mimic high-sugar treats (which is why Oguri Cap devoured so many without suspicion). Once swallowed, the microscopic spores and enzymatic filaments survive the digestive acids in the Uma's stomach and small intestine. Uma digestive systems are efficient and robust (adapted for high-energy racing diets), but the Rootbloom's spores are specifically designed to resist breakdown — a leftover from Agnes's original goal of creating something that could integrate without being destroyed by the host's body.

Initial Colonization (First 4–12 Hours)

The spores breach the intestinal wall using specialized haustoria-like micro-structures (tiny, root-like penetrators). They enter the bloodstream and lymphatic system, hitching a ride via the Uma's powerful circulatory network — which includes an oversized heart and enhanced vascular capacity suited for extreme athletic performance. The spores preferentially target nutrient-rich areas: the digestive tract first, then spreading toward the central nervous system and major muscle groups.

Rewiring Phase (Nighttime Activation, 6–24 Hours Post-Ingestion)

They hijack the Uma's own cells by injecting genetic payloads (engineered RNA and proteins from Agnes's original experiments). This forces host cells to produce plant-like tissue instead of normal Uma flesh.

Vascular Integration: The growing vines tap directly into the Uma's blood vessels and lymphatics, using them as a nutrient highway. The plant siphons sugars, proteins, and minerals while pumping its own sap into the system. This causes an internal sensation and provides the fuel for explosive growth.

Targeted Invasion: The base of the horse-like ears (which have sensitive cartilage and rich blood supply in Uma anatomy) is a weak point. Vines force their way out by splitting the skin, creating external "flowering nodes" for future spore release.

Vocal Cords and Throat: Vines encircle and crush the delicate vocal structures, replacing them with hollow, flexible channels. This prevents screaming while allowing the plant to "breathe" or disperse spores through a gurgling sound.

Eyes: The optic nerves and eye sockets are flooded with sap. The sclera (whites) are hollowed out and filled with dark pigment, while the pupils shrink to glowing white slits optimized for low-light detection of movement (perfect for hunting new hosts at night).

Mouth and Jaw: Enzymes soften and stretch the jaw muscles and skin. Vines push outward, widening the mouth into a petal-like maw for better spore expulsion and feeding.

Musculoskeletal System: Vines wrap around bones and muscles, causing posture changes (forward hunch for "rooting" stability). They rip through skin at elbows, wrists, and spine for external tendrils. Teeth loosen and fall as gums are converted into stem tissue.

Nervous System: The brain is partially preserved but heavily influenced. The Uma's leg strength and speed ironically help the infected move faster during the chase phase.

Why Uma Are Particularly Vulnerable: Umamusume have horse-derived traits, powerful legs for speed, sensitive ears/tails, high metabolism, and robust but specialized physiology. Agnes designed the original strain to exploit exactly these features integrating with muscle tissue for "enhanced performance" and using the rich blood flow for fast spread.

3. Adaptaion: Shadow Observation Network Once fully converted, the infected do not hunt blindly. They enter a passive surveillance state during the day or in well-lit areas. Their pitch black eyes with glowing white pupils are optimized for extreme low-light vision. They can detect the faintest movement or heat signature from dozens of meters away while remaining perfectly still in darkness. The vines beneath their skin act as sensory antennae, picking up vibrations, scents, and even subtle changes in air pressure. Infected will hide in unlit corners, behind doors, or in the overgrown edges of Tracen’s campus, watching their prey from afar for hours. They don’t need to move. They simply observe.

Inheritance of Agnes’s Equations and Problem-Solving: Because the original Nocturne Rootbloom was engineered directly from Agnes Tachyon’s research, the plant carries encoded fragments of her cognitive architecture, her ruthless logic, her ability to break down complex problems into variables, and her talent for predictive modeling. When it takes over the host’s brain, it doesn’t erase everything. Instead, it merges the Uma’s memories with an echo of Agnes’s scientific mind. The infected effectively “remember” Agnes’s equations (formulas for growth rates, infection vectors, nutrient optimization, and behavioral prediction). They treat living Umas like variables in one of Agnes’s experiments.

Mastery of Tracen’s Darkness: The plant evolved to treat the academy’s nighttime environment as its perfect habitat. Tracen after dark has flickering emergency lights, long unlit hallways, and patches of overgrown foliage near Tracen. The infected adapt to this in three ways: Camouflage & Silence, Environmental learning, Patter Recongnition, Behavioral Evolution and prey Specific Tactics. ( This is shown in part 2 & 3. )

(If you have any question, you can put them down in the comments. Also, if you're wondering why agnes is the main problem and why i didn't specify in the first bot... I was saving it for part 4 were Agnes Tachyon, Manhattan Cafe, Jungle Pocket are all in one room and Agnes Tachyon explains the Infected and the plant.)