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1. Big Sister's Obsession by Anonymous

   Fandoms: OMORI (Video Game)  

   • Explicit
   • Rape/Non-Con, Underage Sex
   • F/M
   • Complete Work

   20 Nov 2025

   Tags

   • Rape/Non-Con
   • Underage Sex
   • Mari/Sunny (OMORI)
   • Mari (OMORI)
   • Sunny (OMORI)
   • Mari and Sunny's Parents (OMORI)
   • Siblings
   • Sibling Bonding
   • Sibling Incest
   • Incest
   • Brother/Sister Incest
   • Bad Touch Mari (OMORI)
   • Sexual Abuse
   • Grooming
   • Obsessive Behavior
   • Yandere
   • Shotacon
   • Explicit Sexual Content
   • Alternate Universe
   • Molestation
   • Dubious Consent
   • No Dialogue
   • Unhealthy Relationships
   • Unreliable Narrator
   • POV Alternating

   Summary

   Mari and Sunny were siblings separated at birth. For her entire life, Mari had always wanted a younger brother. It was her greatest wish to have a little brother to love, protect, and take care of. It wasn't until her parents remarried many years later that Mari got her wish.

   Sunny is everything Mari could ever want in a little brother. She adores her little Sunny, and smothers him with all the love she has in her heart.

   Perhaps... too much love. Far more love than any older sister should have for her younger brother. Love that may take Mari down a very dark path.

   Language:

   English

   Words:

   33,239

   Chapters:

   3/3

   Collections:

   1

   Comments:

   60

   Kudos:

   241

   Bookmarks:

   47

   Hits:

   17,389