diff --git a/src/EterLib/ResourceManager.cpp b/src/EterLib/ResourceManager.cpp
index b25355a..4c572f2 100644
--- a/src/EterLib/ResourceManager.cpp
+++ b/src/EterLib/ResourceManager.cpp
@@ -8,7 +8,7 @@
 #include "ResourceManager.h"
 #include "GrpImage.h"
 
-int g_iLoadingDelayTime = 20;
+int g_iLoadingDelayTime = 1;  // Reduced from 20ms to 1ms for faster async loading
 
 const long c_Deleting_Wait_Time = 30000;			// 삭제 대기 시간 (30초)
 const long c_DeletingCountPerFrame = 30;			// 프레임당 체크 리소스 갯수
@@ -16,6 +16,21 @@ const long c_Reference_Decrease_Wait_Time = 30000;	// 선로딩 리소스의 해
 
 CFileLoaderThread CResourceManager::ms_loadingThread;
 
+void CResourceManager::BeginThreadLoading()
+{
+	// Already started in constructor, nothing to do
+}
+
+void CResourceManager::EndThreadLoading()
+{
+	// Wait for all pending requests to complete
+	while (!m_RequestMap.empty() || !m_WaitingMap.empty())
+	{
+		ProcessBackgroundLoading();
+		Sleep(10);
+	}
+}
+
 void CResourceManager::LoadStaticCache(const char* c_szFileName)
 {
 	CResource* pkRes=GetResourcePointer(c_szFileName);
@@ -514,11 +529,11 @@ void CResourceManager::ReserveDeletingResource(CResource * pResource)
 
 CResourceManager::CResourceManager()
 {
-	//ms_loadingThread.Create(0);
+	ms_loadingThread.Create(0);
 }
 
 CResourceManager::~CResourceManager()
 {
 	Destroy();
-	//ms_loadingThread.Shutdown();
+	ms_loadingThread.Shutdown();
 }
diff --git a/src/GameLib/MapOutdoorRender.cpp b/src/GameLib/MapOutdoorRender.cpp
index 5438b7a..15c964b 100644
--- a/src/GameLib/MapOutdoorRender.cpp
+++ b/src/GameLib/MapOutdoorRender.cpp
@@ -40,7 +40,8 @@ void CMapOutdoor::RenderTerrain()
 	//////////////////////////////////////////////////////////////////////////
 	// Push
 	m_PatchVector.clear();
-	
+	m_PatchVector.reserve(256);  // Pre-allocate to avoid reallocations
+
 	__RenderTerrain_RecurseRenderQuadTree(m_pRootNode);
 	
 	// 거리순 정렬
@@ -491,6 +492,7 @@ void CMapOutdoor::RenderArea(bool bRenderAmbience)
 	{
 		static std::vector<CGraphicThingInstance*> s_kVct_pkOpaqueThingInstSort;
 		s_kVct_pkOpaqueThingInstSort.clear();
+		s_kVct_pkOpaqueThingInstSort.reserve(512);  // Pre-allocate to avoid reallocations
 
 		for (int i = 0; i < AROUND_AREA_NUM; ++i)
 		{
@@ -522,6 +524,7 @@ void CMapOutdoor::RenderBlendArea()
 
 	static std::vector<CGraphicThingInstance*> s_kVct_pkBlendThingInstSort;
 	s_kVct_pkBlendThingInstSort.clear();
+	s_kVct_pkBlendThingInstSort.reserve(256);  // Pre-allocate to avoid reallocations
 
 	for (int i = 0; i < AROUND_AREA_NUM; ++i)
 	{
diff --git a/src/UserInterface/InstanceBase.h b/src/UserInterface/InstanceBase.h
index cf2418a..02ab491 100644
--- a/src/UserInterface/InstanceBase.h
+++ b/src/UserInterface/InstanceBase.h
@@ -640,6 +640,7 @@ class CInstanceBase
 		float					NEW_GetDistanceFromDirPixelPosition(const TPixelPosition& c_rkPPosDir);
 		float					NEW_GetDistanceFromDestPixelPosition(const TPixelPosition& c_rkPPosDst);
 		float					NEW_GetDistanceFromDestInstance(CInstanceBase& rkInstDst);
+		float					NEW_GetDistanceFromDestInstanceSquared(CInstanceBase& rkInstDst);  // Optimized: no sqrt
 
 		float					NEW_GetRotation();
 		float					NEW_GetRotationFromDestPixelPosition(const TPixelPosition& c_rkPPosDst);
diff --git a/src/UserInterface/InstanceBaseBattle.cpp b/src/UserInterface/InstanceBaseBattle.cpp
index ba810ed..eb8cfcc 100644
--- a/src/UserInterface/InstanceBaseBattle.cpp
+++ b/src/UserInterface/InstanceBaseBattle.cpp
@@ -91,6 +91,19 @@ float CInstanceBase::NEW_GetDistanceFromDirPixelPosition(const TPixelPosition& c
 	return sqrtf(c_rkPPosDir.x*c_rkPPosDir.x+c_rkPPosDir.y*c_rkPPosDir.y);
 }
 
+// Optimized: Get squared distance (avoid sqrt for comparisons)
+float CInstanceBase::NEW_GetDistanceFromDestInstanceSquared(CInstanceBase& rkInstDst)
+{
+	TPixelPosition kPPosDst;
+	rkInstDst.NEW_GetPixelPosition(&kPPosDst);
+
+	TPixelPosition kPPosCur;
+	NEW_GetPixelPosition(&kPPosCur);
+
+	TPixelPosition kPPosDir = kPPosDst - kPPosCur;
+	return kPPosDir.x * kPPosDir.x + kPPosDir.y * kPPosDir.y;
+}
+
 float CInstanceBase::NEW_GetRotation()
 {
 	float fCurRot=GetRotation();
diff --git a/src/UserInterface/PythonCharacterManager.cpp b/src/UserInterface/PythonCharacterManager.cpp
index 1e0ac34..9edaf23 100644
--- a/src/UserInterface/PythonCharacterManager.cpp
+++ b/src/UserInterface/PythonCharacterManager.cpp
@@ -178,8 +178,10 @@ void CPythonCharacterManager::Update()
 				continue;
 			}
 
-			int nDistance = int(pkInstEach->NEW_GetDistanceFromDestInstance(*pkInstMain));
-			if (nDistance > CHAR_STAGE_VIEW_BOUND + 10)
+			// Optimized: Use squared distance to avoid sqrt
+			float fDistanceSquared = pkInstEach->NEW_GetDistanceFromDestInstanceSquared(*pkInstMain);
+			const float fViewBoundSquared = (CHAR_STAGE_VIEW_BOUND + 10) * (CHAR_STAGE_VIEW_BOUND + 10);
+			if (fDistanceSquared > fViewBoundSquared)
 			{
 				__DeleteBlendOutInstance(pkInstEach);
 				m_kAliveInstMap.erase(c);