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1. Becoming (Gr)Ass Wonder by AuroraTorenaSan, Grimsylvia

   Fandoms: ウマ娘 プリティーダービー | Uma Musume: Pretty Derby (Video Game), ウマ娘 プリティーダービー | Uma Musume: Pretty Derby (Anime), ウマ娘 | Uma Musume - All Media Types  

   • Explicit
   • Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
   • F/F
   • Complete Work

   09 Jun 2026

   Tags

   • Creator Chose Not To Use Archive Warnings
   • No Archive Warnings Apply
   • grass wonder & Trainer
   • Grass Wonder (Uma Musume)
   • Tanino Gimlet (Uma Musume)
   • Daitaku Helios (Uma Musume)
   • Mejiro Palmer (Uma Musume)
   • Trainer (Uma Musume)
   • Original Uma Musume Character(s)
   • Sunday Silence (Uma Musume)
   • Manhattan Cafe (Uma Musume)
   • Wonder Again (Uma Musume)
   • El Condor Pasa (Uma Musume)
   • Symboli Rudolf (Uma Musume)
   • Air Groove (Uma Musume)
   • Rough Sex
   • Vaginal Sex
   • Exhibitionism
   • Degradation
   • Self-Degradation
   • Self-cest
   • HRT | Horse Replacement Therapy (Uma Musume)
   • Masturbation
   • Masturbation in Bathroom
   • Oral Sex
   • Penetrative Sex
   • Sex Toys
   • Transformation
   • Changes to Gender or Sex
   • LGBTQ Character
   • Porn with Feelings
   • Plot What Plot/Porn Without Plot
   • Girl Penis
   • Vaginal Fingering
   • Dirty Talk
   • Ass Expansion
   • Breast Expansion
   • Self Confidence
   • Trans Female Character
   • Breeding Kink
   • Shameless Smut
   • Doppelcest
   • Horsefem | Becoming an Uma Musume (Uma Musume)
   • Threesome - F/F/F
   • Porn with Plot
   • Cuckolding
   • Ghost Sex
   • Dildos
   • Making Love

   Summary

   After discovering a strange trend thanks to El Condor Pasa and her trainer, Grass now wants her trainer to try on her racewear. Something seems off, but what could go wrong?

   Or Grass Wonder accidentally turns her trainer into her slutty twin sister.

   OR Grass Wonder and her succubus doppelganger.

   Who or WHAT will this new girl on the block bring/fuck? Only one way to find out.

   Series

   • Part 3 of Becoming a Horse

   Language:

   English

   Words:

   35,124

   Chapters:

   5/5

   Comments:

   11

   Kudos:

   41

   Bookmarks:

   10

   Hits:

   2,873