diff --git a/include/d/d_com_inf_game.h b/include/d/d_com_inf_game.h
index 7801a6d15..e94e1dd54 100644
--- a/include/d/d_com_inf_game.h
+++ b/include/d/d_com_inf_game.h
@@ -367,7 +367,7 @@ public:
     void setItemNameMessageID(u32 id) { mItemNameMessageID = id; }
 
     s16 getItemKeyNumCount() { return mItemKeyNumCount; }
-    void setItemKeyNumCount(s16 num) { mItemKeyNumCount = num; }
+    void setItemKeyNumCount(s16 num) { mItemKeyNumCount += num; }
 
     void setItemBeastNumCount(int i_idx, s16 num) { mItemBeastNumCounts[i_idx] += num; }
     s16 getItemBeastNumCount(int i_idx) { return mItemBeastNumCounts[i_idx]; }
diff --git a/src/d/d_door.cpp b/src/d/d_door.cpp
index a0b2fe3e3..02b71d368 100644
--- a/src/d/d_door.cpp
+++ b/src/d/d_door.cpp
@@ -438,7 +438,7 @@ void dDoor_key2_c::keyInit(dDoor_info_c* door) {
         if (door->getSwbit() < 0x80)
             dComIfGs_onSwitch(door->getSwbit(), -1);
         if (!mbIsBossDoor)
-            dComIfGp_setItemKeyNumCount(dComIfGp_getItemKeyNumCount() - 1);
+            dComIfGp_setItemKeyNumCount(-1);
         switch (mbIsBossDoor) {
         case 1: fopAcM_seStart(door, JA_SE_OBJ_BOSS_LOCK_OPEN, 0); break;
         default: fopAcM_seStart(door, JA_SE_OBJ_DOOR_CHAIN_OPEN, 0); break;