Ururuc - The Heroine Proceeds Alone Ver.21.08.01 (jap) - Adult Sex Game

Prepare your heroine for the trials ahead, and help her navigate dangerous dungeons.
Battles are 1v1, and some enemies come at the protagonist with devastating H attacks.
If you want to avoid those bad status effects, you'll need to keep her Will high.
Levels gained, stat increases, mana, etc. are all reset after a dungeon-delving section is completed.