diff --git a/src/emscripten/mako.cpp b/src/emscripten/mako.cpp
index 1a71362..252f1d5 100644
--- a/src/emscripten/mako.cpp
+++ b/src/emscripten/mako.cpp
@@ -27,7 +27,10 @@ MAKO::MAKO(NACT* parent, const Config& config) :
 	nact(parent)
 {
 	g_mako = this;
-	strcpy(amus, "AMUS.DAT");
+	amus.open("AMUS.DAT");
+	awav.open("AWAV.DAT");
+	amse.open("AMSE.DAT");
+	mda.open("AMUS.MDA");
 	for (int i = 1; i <= 99; i++)
 		cd_track[i] = 0;
 }
@@ -50,7 +53,7 @@ void MAKO::play_music(int page)
 		EM_ASM_ARGS({ xsystem35.cdPlayer.play($0, $1); },
 					cd_track[page] + 1, next_loop ? 0 : 1);
 	} else {
-		std::vector<uint8_t> data = dri_load(amus, page);
+		std::vector<uint8_t> data = amus.load(page);
 		if (data.empty())
 			return;
 		int rate = EM_ASM_INT({ return xsystem35.audio.enable_audio_hook(); });
@@ -109,9 +112,9 @@ void MAKO::play_pcm(int page, bool loop)
 	};
 
 	// WAV形式 (Only You)
-	std::vector<uint8_t> wav_buffer = dri_load("AWAV.DAT", page);
+	std::vector<uint8_t> wav_buffer = awav.load(page);
 	if (wav_buffer.empty()) {
-		std::vector<uint8_t> buffer = dri_load("AMSE.DAT", page);
+		std::vector<uint8_t> buffer = amse.load(page);
 		if (!buffer.empty()) {
 			// AMSE形式 (乙女戦記)
 			int samples = (buffer.size() - 12) * 2;
diff --git a/src/generic/mako.cpp b/src/generic/mako.cpp
index 856539c..7c99029 100644
--- a/src/generic/mako.cpp
+++ b/src/generic/mako.cpp
@@ -43,8 +43,10 @@ MAKO::MAKO(NACT* parent, const Config& config) :
 	if (!config.playlist.empty() && load_playlist(config.playlist.c_str()))
 		mix_init_flags |= MIX_INIT_MP3 | MIX_INIT_OGG;
 
-	strcpy(amus, "AMUS.DAT");
-	strcpy(amse, "AMSE.DAT"); // unused
+	amus.open("AMUS.DAT");
+	awav.open("AWAV.DAT");
+	amse.open("AMSE.DAT");
+	mda.open("AMUS.MDA");
 	for (int i = 1; i <= 99; i++)
 		cd_track[i] = 0;
 
@@ -117,7 +119,7 @@ void MAKO::play_music(int page)
 			}
 		}
 	} else if (use_fm) {
-		std::vector<uint8_t> data = dri_load(amus, page);
+		std::vector<uint8_t> data = amus.load(page);
 		if (data.empty())
 			return;
 		if (!fm_mutex)
@@ -128,7 +130,7 @@ void MAKO::play_music(int page)
 		SDL_UnlockMutex(fm_mutex);
 		Mix_HookMusic(&FMHook, this);
 	} else if (midi->is_available()) {
-		if (!midi->play(nact, amus, page, next_loop))
+		if (!midi->play(nact, amus, mda, page, next_loop))
 			return;
 	}
 
@@ -193,14 +195,14 @@ void MAKO::play_pcm(int page, bool loop)
 
 	stop_pcm();
 
-	std::vector<uint8_t> buffer = dri_load("AWAV.DAT", page);
+	std::vector<uint8_t> buffer = awav.load(page);
 	if (!buffer.empty()) {
 		// WAV形式 (Only You)
 		mix_chunk = Mix_LoadWAV_RW(SDL_RWFromConstMem(buffer.data(), buffer.size()), 1 /* freesrc */);
 		Mix_PlayChannel(-1, mix_chunk, loop ? -1 : 0);
 		return;
 	}
-	buffer = dri_load("AMSE.DAT", page);
+	buffer = amse.load(page);
 	if (!buffer.empty()) {
 		// AMSE形式 (乙女戦記)
 		int samples = (buffer.size() - 12) * 2;
diff --git a/src/sys/ags.cpp b/src/sys/ags.cpp
index 5311494..2c85843 100644
--- a/src/sys/ags.cpp
+++ b/src/sys/ags.cpp
@@ -159,8 +159,7 @@ AGS::AGS(NACT* parent, const Config& config) : nact(parent), dirty(false)
 
 	// SYSTEM3 初期化
 
-	// ACG.DAT
-	strcpy_s(acg, 16, "ACG.DAT");
+	acg.open("ACG.DAT");
 
 	// パレット
 	memset(program_palette, 0, sizeof(program_palette));
@@ -429,6 +428,22 @@ AGS::~AGS()
 	SDL_DestroyTexture(sdlTexture);
 }
 
+void AGS::set_cg_file(const char *file_name)
+{
+	bmp_prefix = NULL;
+	if (nact->sys_ver == 3) {
+		// あゆみちゃん物語 フルカラー実写版
+		if (!strcmp(file_name, "CGA000.BMP")) {
+			bmp_prefix = "CGA";
+			return;
+		} else if (!strcmp(file_name, "CGB000.BMP")) {
+			bmp_prefix = "CGB";
+			return;
+		}
+	}
+	acg.open(file_name);
+}
+
 void AGS::set_palette(int index, int r, int g, int b)
 {
 	if(index < 16) {
diff --git a/src/sys/ags.h b/src/sys/ags.h
index 8ca0bfa..fa893a2 100644
--- a/src/sys/ags.h
+++ b/src/sys/ags.h
@@ -7,9 +7,11 @@
 #ifndef _AGS_H_
 #define _AGS_H_
 
+#include <memory>
 #include <stdio.h>
 #include "../common.h"
 #include "nact.h"
+#include "dri.h"
 #include <SDL_ttf.h>
 
 #define MAX_CG 10000
@@ -95,6 +97,7 @@ public:
 	void flush_screen(bool update);
 
 	void load_cg(int page, int transparent);
+	void set_cg_file(const char *file_name);
 
 	void set_palette(int index, int r, int g, int b);
 	uint8 get_pixel(int dest, int x, int y);
@@ -136,9 +139,6 @@ public:
 
 	bool dirty;
 
-	// ACG.DAT
-	char acg[16];
-
 	// 画面選択
 	int src_screen;
 	int dest_screen;
@@ -216,6 +216,10 @@ public:
 	// マウスカーソル
 	uint8 cursor_color;
 	int cursor_index;
+
+private:
+	Dri acg;
+	const char* bmp_prefix = NULL;
 };
 
 extern "C" void ags_setAntialiasedStringMode(int on);
diff --git a/src/sys/ags_draw.cpp b/src/sys/ags_draw.cpp
index 90b5a0d..81c9885 100644
--- a/src/sys/ags_draw.cpp
+++ b/src/sys/ags_draw.cpp
@@ -15,21 +15,13 @@
 
 void AGS::load_cg(int page, int transparent)
 {
-	if (nact->sys_ver == 3) {
-		// あゆみちゃん物語 フルカラー実写版
-		if(strncmp(acg, "CGA000.BMP", 10) == 0) {
-			char file_name[16];
-			snprintf(file_name, sizeof(file_name), "CGA%03d.BMP", page);
-			load_bmp(file_name);
-			return;
-		} else if(strncmp(acg, "CGB000.BMP", 10) == 0) {
-			char file_name[16];
-			snprintf(file_name, sizeof(file_name), "CGB%03d.BMP", page);
-			load_bmp(file_name);
-			return;
-		}
+	if (bmp_prefix) {
+		char file_name[16];
+		snprintf(file_name, sizeof(file_name), "%s%03d.BMP", bmp_prefix, page);
+		load_bmp(file_name);
+		return;
 	}
-	std::vector<uint8_t> data = dri_load(acg, page);
+	std::vector<uint8_t> data = acg.load(page);
 	if (data.empty())
 		return;
 	switch (nact->sys_ver) {
diff --git a/src/sys/dri.cpp b/src/sys/dri.cpp
index 7c4873f..0c45391 100644
--- a/src/sys/dri.cpp
+++ b/src/sys/dri.cpp
@@ -5,83 +5,63 @@
 */
 
 #include "dri.h"
+#include <memory>
 #include <string.h>
 #include "crc32.h"
 #include "../fileio.h"
 
-std::vector<uint8> dri_load(const char* file_name, int page)
+void Dri::open(const char* file_name)
 {
-	char tmp_name[20];
-	strcpy_s(tmp_name, sizeof(tmp_name), file_name);
+	link_table.clear();
+	fname = file_name;
+	fname[0] = 'A';
 
-	FILEIO* fio = new FILEIO();
-
-	// ページの位置を取得
-	tmp_name[0] = 'A';
-	if(!fio->Fopen(tmp_name, FILEIO_READ_BINARY)) {
-		delete fio;
-		return {};
-	}
+	auto fio = std::make_unique<FILEIO>();
+	if (!fio->Fopen(fname.c_str(), FILEIO_READ_BINARY))
+		return;
 
 	int link_sector = fio->Fgetc();
 	link_sector |= fio->Fgetc() << 8;
 	int data_sector = fio->Fgetc();
 	data_sector |= fio->Fgetc() << 8;
 
-	if(page > (data_sector - link_sector) * 128 - 1) {
-		// ページ番号不正
-		fio->Fclose();
-		delete fio;
+	link_table.resize((data_sector - link_sector) * 256);
+	fio->Fseek((link_sector - 1) * 256, FILEIO_SEEK_SET);
+	fio->Fread(link_table.data(), 256, data_sector - link_sector);
+}
+
+std::vector<uint8> Dri::load(int page)
+{
+	if (static_cast<size_t>(page) >= link_table.size() / 2)
 		return {};
-	}
 
-	fio->Fseek((link_sector - 1) * 256 + (page - 1) * 2, FILEIO_SEEK_SET);
-	int disk_index = fio->Fgetc();
-	int link_index = fio->Fgetc();
-
-	if(disk_index == 0 || disk_index == 0x1a) {
-		// 欠番
-		fio->Fclose();
-		delete fio;
+	int disk_index = link_table[(page - 1) * 2];
+	int link_index = link_table[(page - 1) * 2 + 1];
+	if (disk_index == 0 || disk_index == 0x1a)
 		return {};
-	}
 
-	// A??.DAT以外にリンクされている場合はファイルを開き直す
-	if(disk_index != 1) {
-		tmp_name[0] = 'A' + disk_index - 1;
-		fio->Fclose();
-		if(!fio->Fopen(tmp_name, FILEIO_READ_BINARY)) {
-			delete fio;
-			return {};
-		}
-	}
+	auto fio = std::make_unique<FILEIO>();
+	fname[0] = 'A' + disk_index - 1;
+	if (!fio->Fopen(fname.c_str(), FILEIO_READ_BINARY))
+		return {};
 
-	// データ取得
 	fio->Fseek(link_index * 2, FILEIO_SEEK_SET);
 	int start_sector = fio->Fgetc();
 	start_sector |= fio->Fgetc() << 8;
 	int end_sector = fio->Fgetc();
 	end_sector |= fio->Fgetc() << 8;
-
-	int size = (end_sector - start_sector) * 256;
-	if (size == 0) {
-		// サイズ不正
-		fio->Fclose();
-		delete fio;
+	if (end_sector <= start_sector)
 		return {};
-	}
 
-	std::vector<uint8_t> buffer(size);
+	std::vector<uint8_t> buffer((end_sector - start_sector) * 256);
 	fio->Fseek((start_sector - 1) * 256, FILEIO_SEEK_SET);
 	fio->Fread(buffer.data(), 256, end_sector - start_sector);
 
-	fio->Fclose();
-	delete fio;
-
 	return buffer;
 }
 
-std::vector<uint8> dri_load_mda(uint32_t crc32_a, uint32_t crc32_b, int page)
+// static
+std::vector<uint8> Dri::load_mda(uint32_t crc32_a, uint32_t crc32_b, int page)
 {
 	// データ取得
 	const char* name = NULL;
diff --git a/src/sys/dri.h b/src/sys/dri.h
index a2e814b..b60c461 100644
--- a/src/sys/dri.h
+++ b/src/sys/dri.h
@@ -7,10 +7,20 @@
 #ifndef _DRI_H_
 #define _DRI_H_
 
+#include <string>
 #include <stdint.h>
 #include <vector>
 
-std::vector<uint8_t> dri_load(const char* file_name, int page);
-std::vector<uint8_t> dri_load_mda(uint32_t crc32_a, uint32_t crc32_b, int page);
+class Dri {
+public:
+	void open(const char* file_name);
+	std::vector<uint8_t> load(int page);
+
+	static std::vector<uint8_t> load_mda(uint32_t crc32_a, uint32_t crc32_b, int page);
+
+private:
+	std::string fname;
+	std::vector<uint8_t> link_table;
+};
 
 #endif
diff --git a/src/sys/mako.h b/src/sys/mako.h
index 0847c1e..cda2a3a 100644
--- a/src/sys/mako.h
+++ b/src/sys/mako.h
@@ -7,12 +7,14 @@
 #ifndef _MAKO_H_
 #define _MAKO_H_
 
+#include <memory>
 #include <vector>
 #include <stdio.h>
 #include <limits.h>
 #include <math.h>
 #include "../common.h"
 #include "nact.h"
+#include "dri.h"
 
 enum BGMDevice {
 	BGM_FM,
@@ -46,9 +48,10 @@ public:
 
 	bool use_fm;
 
-	// AMUS.DAT, AMSE.DAT
-	char amus[16];
-	char amse[16];
+	Dri amus;
+	Dri awav;
+	Dri amse;
+	Dri mda;
 
 	int current_music;
 	int next_loop;		// Y19
@@ -57,7 +60,7 @@ private:
 	NACT* nact;
 	int cd_track[100];	// Z
 
-#if !defined(__EMSCRIPTEN__)
+#ifndef __EMSCRIPTEN__
 	bool load_playlist(const char* path);
 
 	std::vector<const char*> playlist;
diff --git a/src/sys/mako_midi.cpp b/src/sys/mako_midi.cpp
index 9b3dba5..14b5c16 100644
--- a/src/sys/mako_midi.cpp
+++ b/src/sys/mako_midi.cpp
@@ -93,7 +93,7 @@ void stop_midi()
 
 class Playback {
 public:
-	static std::unique_ptr<Playback> create(NACT* nact, char* amus, int page, int loop, int seq);
+	static std::unique_ptr<Playback> create(NACT* nact, Dri& amus, Dri& mda, int page, int loop, int seq);
 	Playback(uint32_t crc32_a, int loop, int seq) : crc32_a(crc32_a), loop_(loop), seq_(seq) {}
 	bool load_mml(const std::vector<uint8_t>& data);
 	void load_mda(const std::vector<uint8_t>& data);
@@ -379,23 +379,20 @@ bool Playback::play_midi(SDL_atomic_t* current_loop, SDL_atomic_t* current_mark)
 }
 
 //static
-std::unique_ptr<Playback> Playback::create(NACT* nact, char* amus, int page, int loop, int seq)
+std::unique_ptr<Playback> Playback::create(NACT* nact, Dri& amus, Dri& mda, int page, int loop, int seq)
 {
 	auto playback = std::make_unique<Playback>(nact->crc32_a, loop, seq);
 
-	std::vector<uint8_t> data = dri_load(amus, page);
+	std::vector<uint8_t> data = amus.load(page);
 	if (data.empty())
 		return nullptr;
 	if (!playback->load_mml(data))
 		return nullptr;
 
 	// Load MDA
-	char path[16];
-	strcpy_s(path, 16, amus);
-	strcpy(path + strlen(path) - 3, "MDA");
-	data = dri_load(path, page);
+	data = mda.load(page);
 	if (data.empty())
-		data = dri_load_mda(nact->crc32_a, nact->crc32_b, page);
+		data = Dri::load_mda(nact->crc32_a, nact->crc32_b, page);
 	playback->load_mda(data);
 
 	return playback;
@@ -663,10 +660,10 @@ bool MAKOMidi::is_available()
 	return !!midiout;
 }
 
-bool MAKOMidi::play(NACT* nact, char* amus, int page, int loop)
+bool MAKOMidi::play(NACT* nact, Dri& amus, Dri& mda, int page, int loop)
 {
 	int seq = ++next_seq;
-	auto playback = Playback::create(nact, amus, page, loop, seq);
+	auto playback = Playback::create(nact, amus, mda, page, loop, seq);
 	if (!playback)
 		return false;
 	SDL_AtomicSet(&current_seq, seq);
diff --git a/src/sys/mako_midi.h b/src/sys/mako_midi.h
index 87c6c82..41a0712 100644
--- a/src/sys/mako_midi.h
+++ b/src/sys/mako_midi.h
@@ -7,6 +7,7 @@
 #include "../common.h"
 
 class NACT;
+class Dri;
 
 #ifdef USE_MIDI
 
@@ -15,7 +16,7 @@ public:
 	explicit MAKOMidi(int device);
 	~MAKOMidi();
 	bool is_available();
-	bool play(NACT* nact, char* amus, int page, int loop);
+	bool play(NACT* nact, Dri& amus, Dri& mda, int page, int loop);
 	void stop();
 	bool is_playing();
 	void get_mark(int* mark, int* loop);
@@ -40,7 +41,7 @@ class MAKOMidi {
 public:
 	explicit MAKOMidi(int device) {}
 	bool is_available() { return false; }
-	bool play(NACT* nact, char* amus, int page, int loop) { return false; }
+	bool play(NACT* nact, Dri& amus, Dri& mda, int page, int loop) { return false; }
 	void stop() {}
 	bool is_playing() { return false; }
 	void get_mark(int* mark, int* loop) { *mark = *loop = 0; }
diff --git a/src/sys/nact.cpp b/src/sys/nact.cpp
index 265c603..dd7695a 100644
--- a/src/sys/nact.cpp
+++ b/src/sys/nact.cpp
@@ -54,9 +54,9 @@ NACT::NACT(int sys_ver, uint32 crc32_a, uint32 crc32_b, const Config& config)
 
 	// ADISK.DAT
 	if (crc32_a == CRC32_PROG_OMAKE)
-		strcpy_s(adisk, 16, "AGAME.DAT");
+		adisk.open("AGAME.DAT");
 	else
-		strcpy_s(adisk, 16, "ADISK.DAT");
+		adisk.open("ADISK.DAT");
 
 	// シナリオ管理
 	load_scenario(0);
@@ -387,7 +387,7 @@ void NACT::text_wait()
 
 void NACT::load_scenario(int page)
 {
-	scenario_data = dri_load(adisk, page + 1);
+	scenario_data = adisk.load(page + 1);
 	if (scenario_data.empty()) {
 		fatal("Cannot load scenario %d", page);
 	}
diff --git a/src/sys/nact.h b/src/sys/nact.h
index c87b66b..dd73504 100644
--- a/src/sys/nact.h
+++ b/src/sys/nact.h
@@ -13,6 +13,7 @@
 #include <stdio.h>
 #include "../common.h"
 #include "config.h"
+#include "dri.h"
 
 #define RND var[ 0]
 #define D01 var[ 1]
@@ -111,8 +112,7 @@ protected:
 	void execute();
 	void load_scenario(int page);
 
-	// ADISK.DAT, ASLEEP.DAT
-	char adisk[16];
+	Dri adisk;
 
 	// シナリオデータ
 	std::vector<uint8_t> scenario_data;
diff --git a/src/sys/nact_sys3.cpp b/src/sys/nact_sys3.cpp
index acfe978..f641b93 100644
--- a/src/sys/nact_sys3.cpp
+++ b/src/sys/nact_sys3.cpp
@@ -744,13 +744,15 @@ void NACT_Sys3::cmd_m()
 	if(1 <= tvar_index && tvar_index <= 10) {
 		memcpy(tvar[tvar_index - 1], string, 22);
 	} else if(tvar_index == 31) {
-		strcpy_s(adisk, 16, string);
+		adisk.open(string);
 	} else if(tvar_index == 32) {
-		strcpy_s(ags->acg, 16, string);
+		ags->set_cg_file(string);
 	} else if(tvar_index == 33) {
-		strcpy_s(mako->amus, 16, string);
+		mako->amus.open(string);
+		strcpy(string + strlen(string) - 3, "MDA");
+		mako->mda.open(string);
 	} else if(tvar_index == 34) {
-		strcpy_s(mako->amse, 16, string);
+		// mako->amse.open(string);
 	}
 }
 
@@ -1370,7 +1372,7 @@ void NACT_Sys3::cmd_y()
 			break;
 		case 250:
 #if 0
-			if(FILEIO::GetRootPath()[1] == ':') {
+			if(FILEIO::GetRootPath()[1] == ':') {
 				_TCHAR root_path[4];
 				root_path[0] = FILEIO::GetRootPath()[0];
 				root_path[1] = ':';
diff --git a/src/win/mako.cpp b/src/win/mako.cpp
index 62be19d..ca72cd5 100644
--- a/src/win/mako.cpp
+++ b/src/win/mako.cpp
@@ -209,8 +209,10 @@ MAKO::MAKO(NACT* parent, const Config& config) :
 	if (!config.playlist.empty())
 		load_playlist(config.playlist.c_str());
 
-	strcpy_s(amus, 16, "AMUS.DAT");
-	strcpy_s(amse, 16, "AMSE.DAT");	// 実際には使わない
+	amus.open("AMUS.DAT");
+	awav.open("AWAV.DAT");
+	amse.open("AMSE.DAT");
+	mda.open("AMUS.MDA");
 
 	for(int i = 1; i <= 99; i++) {
 		cd_track[i] = 0;
@@ -288,7 +290,7 @@ void MAKO::play_music(int page)
 			return;
 		music = new Music(playlist[track], next_loop);
 	} else if (use_fm) {
-		std::vector<uint8_t> data = dri_load(amus, page);
+		std::vector<uint8_t> data = amus.load(page);
 		if (data.empty())
 			return;
 
@@ -297,7 +299,7 @@ void MAKO::play_music(int page)
 		SDL_UnlockMutex(fm_mutex);
 		SDL_PauseAudio(0);
 	} else if (midi->is_available()) {
-		if (!midi->play(nact, amus, page, next_loop))
+		if (!midi->play(nact, amus, mda, page, next_loop))
 			return;
 	}
 	current_music = page;
@@ -419,9 +421,9 @@ void MAKO::play_pcm(int page, bool loop)
 	stop_pcm();
 
 	// WAV形式 (Only You)
-	std::vector<uint8_t> wav_buffer = dri_load("AWAV.DAT", page);
+	std::vector<uint8_t> wav_buffer = awav.load(page);
 	if (wav_buffer.empty()) {
-		std::vector<uint8_t> buffer = dri_load("AMSE.DAT", page);
+		std::vector<uint8_t> buffer = amse.load(page);
 		if (!buffer.empty()) {
 			// AMSE形式 (乙女戦記)
 			int samples = (static_cast<int>(buffer.size()) - 12) * 2;