List item in Dark Realm:

Talisman:
For reviving your character (Samanosuke or Kaede)

Medicine:
Restore strength to it maximum

Herb:
Restore a little of strength

Fluorites:
Use to unlocked the Oni-spirits mini-game

Soul Absorber:
Automatically absorb the enemy's soul

Bishamon Flute:
Use to open the door to get the Bishamon Sword