Adult PC Game: A Simple Life with My Unobtrusive Sister Ver.0.85 by Countercurrent Tea Party Archive

Living with your sister x action battle x roguelike x open world fantasy RPG game!
The player plays a solo adventurer in the dungeon while living with his sister.
In order to cure his sister's special constitution,
he constantly searches for materials to make the all-purpose elixir "red cerebrospinal fluid" in the Abyss.
If he cannot complete it within the time limit, his sister...!​

A Simple Life with My Unobtrusive Sister Ver.0.85 by Countercurrent Tea Party Gameplay Preview