diff --git a/src/sys/nact.cpp b/src/sys/nact.cpp
index a3c887f..4bc0868 100644
--- a/src/sys/nact.cpp
+++ b/src/sys/nact.cpp
@@ -144,7 +144,17 @@ void NACT::mainloop()
 	int sleep_cnt = 0;
 
 	while(!terminate) {
-		execute();
+		switch (sys_ver) {
+		case 1:
+			execute(static_cast<NACT_Sys1*>(this));
+			break;
+		case 2:
+			execute(static_cast<NACT_Sys2*>(this));
+			break;
+		case 3:
+			execute(static_cast<NACT_Sys3*>(this));
+			break;
+		}
 		// 512コマンド実行毎にSleep(10)
 		if(!(sleep_cnt = (sleep_cnt + 1) & 0x1ff)) {
 			SDL_Delay(10);
@@ -154,7 +164,8 @@ void NACT::mainloop()
 
 // コマンドパーサ
 
-void NACT::execute()
+template <class T>
+void NACT::execute(T* impl)
 {
 	// アドレスの確認
 	if(scenario_addr < 2 || scenario_addr >= scenario_size) {
@@ -171,7 +182,7 @@ void NACT::execute()
 	}
 
 	if(sys_ver == 1 && scenario_page == 0 && scenario_addr == 2) {
-		opening();
+		impl->opening();
 	}
 
 	// １コマンド実行
@@ -185,117 +196,117 @@ void NACT::execute()
 	if(verb_obj && cmd != '[' && cmd != ':') {
 		// 動詞-目的語メニューの表示
 		scenario_addr--;
-		cmd_open_verb();
+		impl->cmd_open_verb();
 		return;
 	}
 
 	switch(cmd) {
 		case '!':
-			cmd_calc();
+			impl->cmd_calc();
 			break;
 		case '{':
-			cmd_branch();
+			impl->cmd_branch();
 			break;
 		case '}':
 			break;
 		case '@':
-			cmd_label_jump();
+			impl->cmd_label_jump();
 			break;
 		case '\\':
-			cmd_label_call();
+			impl->cmd_label_call();
 			break;
 		case '&':
-			cmd_page_jump();
+			impl->cmd_page_jump();
 			break;
 		case '%':
-			cmd_page_call();
+			impl->cmd_page_call();
 			break;
 		case '$':
-			cmd_set_menu();
+			impl->cmd_set_menu();
 			break;
 		case '[':
-			cmd_set_verbobj();
+			impl->cmd_set_verbobj();
 			break;
 		case ':':
-			cmd_set_verbobj2();
+			impl->cmd_set_verbobj2();
 			break;
 		case ']':
-			cmd_open_menu();
+			impl->cmd_open_menu();
 			break;
 		case 'A':
-			cmd_a();
+			impl->cmd_a();
 			break;
 		case 'B':
-			cmd_b();
+			impl->cmd_b();
 			break;
 		case 'D':
-			cmd_d();
+			impl->cmd_d();
 			break;
 		case 'E':
-			cmd_e();
+			impl->cmd_e();
 			break;
 		case 'F':
-			cmd_f();
+			impl->cmd_f();
 			break;
 		case 'G':
-			cmd_g();
+			impl->cmd_g();
 			break;
 		case 'H':
-			cmd_h();
+			impl->cmd_h();
 			break;
 		case 'I':
-			cmd_i();
+			impl->cmd_i();
 			break;
 		case 'J':
-			cmd_j();
+			impl->cmd_j();
 			break;
 		case 'K':
-			cmd_k();
+			impl->cmd_k();
 			break;
 		case 'L':
-			cmd_l();
+			impl->cmd_l();
 			break;
 		case 'M':
-			cmd_m();
+			impl->cmd_m();
 			break;
 		case 'N':
-			cmd_n();
+			impl->cmd_n();
 			break;
 		case 'O':
-			cmd_o();
+			impl->cmd_o();
 			break;
 		case 'P':
-			cmd_p();
+			impl->cmd_p();
 			break;
 		case 'Q':
-			cmd_q();
+			impl->cmd_q();
 			break;
 		case 'R':
-			cmd_r();
+			impl->cmd_r();
 			break;
 		case 'S':
-			cmd_s();
+			impl->cmd_s();
 			break;
 		case 'T':
-			cmd_t();
+			impl->cmd_t();
 			break;
 		case 'U':
-			cmd_u();
+			impl->cmd_u();
 			break;
 		case 'V':
-			cmd_v();
+			impl->cmd_v();
 			break;
 		case 'W':
-			cmd_w();
+			impl->cmd_w();
 			break;
 		case 'X':
-			cmd_x();
+			impl->cmd_x();
 			break;
 		case 'Y':
-			cmd_y();
+			impl->cmd_y();
 			break;
 		case 'Z':
-			cmd_z();
+			impl->cmd_z();
 			break;
 		default:
 			if(cmd == 0x20 || (0xa1 <= cmd && cmd <= 0xdd)) {
diff --git a/src/sys/nact.h b/src/sys/nact.h
index 235267d..bb6b724 100644
--- a/src/sys/nact.h
+++ b/src/sys/nact.h
@@ -85,14 +85,14 @@ class NACT
 public:
 	static NACT* create(const char* game_id, const char* font_file, const char* playlist);
 	NACT(int sys_ver, uint32 crc32, const char* font_file, const char* playlist);
-	virtual ~NACT();
+	~NACT();
 
 protected:
 	AGS* ags;
 	MAKO* mako;
 
 	// コマンドパーサ
-	void execute();
+	template <class T> void execute(T* impl);
 	void load_scenario(int page);
 
 	bool fatal_error = false;
@@ -121,51 +121,7 @@ protected:
 	char tvar_stack[30][10][22];
 //	int tvar_index;
 
-	// コマンド
-	virtual void cmd_calc() = 0;
-
-	virtual void cmd_branch() = 0;
-	virtual void cmd_label_jump() = 0;
-	virtual void cmd_label_call() = 0;
-	virtual void cmd_page_jump() = 0;
-	virtual void cmd_page_call() = 0;
-
-	virtual void cmd_set_menu() = 0;
-	virtual void cmd_open_menu() = 0;
-
-	virtual void cmd_set_verbobj() = 0;
-	virtual void cmd_set_verbobj2() = 0;
-	virtual void cmd_open_verb() = 0;
-	virtual void cmd_open_obj(int verb) = 0;
-
-	virtual void cmd_a() = 0;
-	virtual void cmd_b() = 0;
-	virtual void cmd_d() = 0;
-	virtual void cmd_e() = 0;
-	virtual void cmd_f() = 0;
-	virtual void cmd_g() = 0;
-	virtual void cmd_h() = 0;
-	virtual void cmd_i() = 0;
-	virtual void cmd_j() = 0;
-	virtual void cmd_k() = 0;
-	virtual void cmd_l() = 0;
-	virtual void cmd_m() = 0;
-	virtual void cmd_n() = 0;
-	virtual void cmd_o() = 0;
-	virtual void cmd_p() = 0;
-	virtual void cmd_q() = 0;
-	virtual void cmd_r() = 0;
-	virtual void cmd_s() = 0;
-	virtual void cmd_t() = 0;
-	virtual void cmd_u() = 0;
-	virtual void cmd_v() = 0;
-	virtual void cmd_w() = 0;
-	virtual void cmd_x() = 0;
-	virtual void cmd_y() = 0;
-	virtual void cmd_z() = 0;
-
 	// SYSTEM1 ----
-	virtual void opening() {}
 	int menu_max;	// メニューの改ページ
 
 	// DPS
@@ -202,10 +158,12 @@ protected:
 	int pcm[MAX_PCM];
 
 	// 下位関数
-	virtual uint16 cali() = 0;
-	virtual uint16 cali2() = 0;
-	virtual uint8 getd() = 0;
-	virtual uint16 getw() = 0;
+	uint8 getd() { return scenario_data[scenario_addr++]; }
+	uint16 getw() {
+		uint16 val = scenario_data[scenario_addr] | (scenario_data[scenario_addr + 1] << 8);
+		scenario_addr += 2;
+		return val;
+	}
 
 	uint16 random(uint16 range);
 	uint32 seed;
@@ -264,141 +222,139 @@ public:
 class NACT_Sys1 : public NACT {
 public:
 	NACT_Sys1(uint32 crc32, const char* font_file, const char* playlist);
-	void cmd_calc() override;
-	void cmd_branch() override;
-	void cmd_label_jump() override;
-	void cmd_label_call() override;
-	void cmd_page_jump() override;
-	void cmd_page_call() override;
-	void cmd_set_menu() override;
-	void cmd_open_menu() override;
-	void cmd_set_verbobj() override;
-	void cmd_set_verbobj2() override;
-	void cmd_open_verb() override;
-	void cmd_open_obj(int verb) override;
-	void cmd_a() override;
-	void cmd_b() override;
-	void cmd_d() override;
-	void cmd_e() override;
-	void cmd_f() override;
-	void cmd_g() override;
-	void cmd_h() override;
-	void cmd_i() override;
-	void cmd_j() override;
-	void cmd_k() override;
-	void cmd_l() override;
-	void cmd_m() override;
-	void cmd_n() override;
-	void cmd_o() override;
-	void cmd_p() override;
-	void cmd_q() override;
-	void cmd_r() override;
-	void cmd_s() override;
-	void cmd_t() override;
-	void cmd_u() override;
-	void cmd_v() override;
-	void cmd_w() override;
-	void cmd_x() override;
-	void cmd_y() override;
-	void cmd_z() override;
-	void opening() override;
-	uint16 cali() override;
-	uint16 cali2() override;
-	uint8 getd() override;
-	uint16 getw() override;
+	void cmd_calc();
+	void cmd_branch();
+	void cmd_label_jump();
+	void cmd_label_call();
+	void cmd_page_jump();
+	void cmd_page_call();
+	void cmd_set_menu();
+	void cmd_open_menu();
+	void cmd_set_verbobj();
+	void cmd_set_verbobj2();
+	void cmd_open_verb();
+	void cmd_open_obj(int verb);
+	void cmd_a();
+	void cmd_b();
+	void cmd_d();
+	void cmd_e();
+	void cmd_f();
+	void cmd_g();
+	void cmd_h();
+	void cmd_i();
+	void cmd_j();
+	void cmd_k();
+	void cmd_l();
+	void cmd_m();
+	void cmd_n();
+	void cmd_o();
+	void cmd_p();
+	void cmd_q();
+	void cmd_r();
+	void cmd_s();
+	void cmd_t();
+	void cmd_u();
+	void cmd_v();
+	void cmd_w();
+	void cmd_x();
+	void cmd_y();
+	void cmd_z();
+	void opening();
+private:
+	uint16 cali();
+	uint16 cali2();
 };
 
 class NACT_Sys2 : public NACT {
 public:
 	NACT_Sys2(uint32 crc32, const char* font_file, const char* playlist);
-	void cmd_calc() override;
-	void cmd_branch() override;
-	void cmd_label_jump() override;
-	void cmd_label_call() override;
-	void cmd_page_jump() override;
-	void cmd_page_call() override;
-	void cmd_set_menu() override;
-	void cmd_open_menu() override;
-	void cmd_set_verbobj() override;
-	void cmd_set_verbobj2() override;
-	void cmd_open_verb() override;
-	void cmd_open_obj(int verb) override;
-	void cmd_a() override;
-	void cmd_b() override;
-	void cmd_d() override;
-	void cmd_e() override;
-	void cmd_f() override;
-	void cmd_g() override;
-	void cmd_h() override;
-	void cmd_i() override;
-	void cmd_j() override;
-	void cmd_k() override;
-	void cmd_l() override;
-	void cmd_m() override;
-	void cmd_n() override;
-	void cmd_o() override;
-	void cmd_p() override;
-	void cmd_q() override;
-	void cmd_r() override;
-	void cmd_s() override;
-	void cmd_t() override;
-	void cmd_u() override;
-	void cmd_v() override;
-	void cmd_w() override;
-	void cmd_x() override;
-	void cmd_y() override;
-	void cmd_z() override;
-	uint16 cali() override;
-	uint16 cali2() override;
-	uint8 getd() override;
-	uint16 getw() override;
+	void cmd_calc();
+	void cmd_branch();
+	void cmd_label_jump();
+	void cmd_label_call();
+	void cmd_page_jump();
+	void cmd_page_call();
+	void cmd_set_menu();
+	void cmd_open_menu();
+	void cmd_set_verbobj();
+	void cmd_set_verbobj2();
+	void cmd_open_verb();
+	void cmd_open_obj(int verb);
+	void cmd_a();
+	void cmd_b();
+	void cmd_d();
+	void cmd_e();
+	void cmd_f();
+	void cmd_g();
+	void cmd_h();
+	void cmd_i();
+	void cmd_j();
+	void cmd_k();
+	void cmd_l();
+	void cmd_m();
+	void cmd_n();
+	void cmd_o();
+	void cmd_p();
+	void cmd_q();
+	void cmd_r();
+	void cmd_s();
+	void cmd_t();
+	void cmd_u();
+	void cmd_v();
+	void cmd_w();
+	void cmd_x();
+	void cmd_y();
+	void cmd_z();
+	void opening() {}
+private:
+	uint16 cali();
+	uint16 cali2();
 };
 
 class NACT_Sys3 : public NACT {
 public:
 	NACT_Sys3(uint32 crc32, const char* font_file, const char* playlist);
-	void cmd_calc() override;
-	void cmd_branch() override;
-	void cmd_label_jump() override;
-	void cmd_label_call() override;
-	void cmd_page_jump() override;
-	void cmd_page_call() override;
-	void cmd_set_menu() override;
-	void cmd_open_menu() override;
-	void cmd_set_verbobj() override;
-	void cmd_set_verbobj2() override;
-	void cmd_open_verb() override;
-	void cmd_open_obj(int verb) override;
-	void cmd_a() override;
-	void cmd_b() override;
-	void cmd_d() override;
-	void cmd_e() override;
-	void cmd_f() override;
-	void cmd_g() override;
-	void cmd_h() override;
-	void cmd_i() override;
-	void cmd_j() override;
-	void cmd_k() override;
-	void cmd_l() override;
-	void cmd_m() override;
-	void cmd_n() override;
-	void cmd_o() override;
-	void cmd_p() override;
-	void cmd_q() override;
-	void cmd_r() override;
-	void cmd_s() override;
-	void cmd_t() override;
-	void cmd_u() override;
-	void cmd_v() override;
-	void cmd_w() override;
-	void cmd_x() override;
-	void cmd_y() override;
-	void cmd_z() override;
-	uint16 cali() override;
-	uint16 cali2() override;
-	uint8 getd() override;
-	uint16 getw() override;
+	void cmd_calc();
+	void cmd_branch();
+	void cmd_label_jump();
+	void cmd_label_call();
+	void cmd_page_jump();
+	void cmd_page_call();
+	void cmd_set_menu();
+	void cmd_open_menu();
+	void cmd_set_verbobj();
+	void cmd_set_verbobj2();
+	void cmd_open_verb();
+	void cmd_open_obj(int verb);
+	void cmd_a();
+	void cmd_b();
+	void cmd_d();
+	void cmd_e();
+	void cmd_f();
+	void cmd_g();
+	void cmd_h();
+	void cmd_i();
+	void cmd_j();
+	void cmd_k();
+	void cmd_l();
+	void cmd_m();
+	void cmd_n();
+	void cmd_o();
+	void cmd_p();
+	void cmd_q();
+	void cmd_r();
+	void cmd_s();
+	void cmd_t();
+	void cmd_u();
+	void cmd_v();
+	void cmd_w();
+	void cmd_x();
+	void cmd_y();
+	void cmd_z();
+	void opening() {}
 private:
+	uint16 cali();
+	uint16 cali2();
 	int menu_select(int num_items);
 };
 
diff --git a/src/sys/nact_sys1.cpp b/src/sys/nact_sys1.cpp
index 23cec25..97ec943 100644
--- a/src/sys/nact_sys1.cpp
+++ b/src/sys/nact_sys1.cpp
@@ -1579,16 +1579,3 @@ uint16 NACT_Sys1::cali2()
 	}
 	return val;
 }
-
-uint8 NACT_Sys1::getd()
-{
-	return scenario_data[scenario_addr++];
-}
-
-uint16 NACT_Sys1::getw()
-{
-	uint16 val = scenario_data[scenario_addr] | (scenario_data[scenario_addr + 1] << 8);
-	scenario_addr += 2;
-	return val;
-}
-
diff --git a/src/sys/nact_sys2.cpp b/src/sys/nact_sys2.cpp
index c538021..4efa2ae 100644
--- a/src/sys/nact_sys2.cpp
+++ b/src/sys/nact_sys2.cpp
@@ -1661,16 +1661,3 @@ uint16 NACT_Sys2::cali2()
 	}
 	return val;
 }
-
-uint8 NACT_Sys2::getd()
-{
-	return scenario_data[scenario_addr++];
-}
-
-uint16 NACT_Sys2::getw()
-{
-	uint16 val = scenario_data[scenario_addr] | (scenario_data[scenario_addr + 1] << 8);
-	scenario_addr += 2;
-	return val;
-}
-
diff --git a/src/sys/nact_sys3.cpp b/src/sys/nact_sys3.cpp
index d2ae8d1..295fdb9 100644
--- a/src/sys/nact_sys3.cpp
+++ b/src/sys/nact_sys3.cpp
@@ -1775,16 +1775,3 @@ uint16 NACT_Sys3::cali2()
 	}
 	return val;
 }
-
-uint8 NACT_Sys3::getd()
-{
-	return scenario_data[scenario_addr++];
-}
-
-uint16 NACT_Sys3::getw()
-{
-	uint16 val = scenario_data[scenario_addr] | (scenario_data[scenario_addr + 1] << 8);
-	scenario_addr += 2;
-	return val;
-}
-