diff --git a/CMakeLists.txt b/CMakeLists.txt
index 23cd7d0..944eacb 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -217,6 +217,7 @@ target_sources(system3 PRIVATE
   src/sys/game_id.cpp
   src/sys/msgskip.cpp
   src/sys/nact.cpp
+  src/sys/nact_gakuenking.cpp
   src/sys/nact_input.cpp
   src/sys/nact_sys1.cpp
   src/sys/nact_sys2.cpp
diff --git a/src/sys/ags_window.cpp b/src/sys/ags_window.cpp
index a0c7b14..7959920 100644
--- a/src/sys/ags_window.cpp
+++ b/src/sys/ags_window.cpp
@@ -96,7 +96,14 @@ void AGS::init_windows()
 			}
 			break;
 		case GameId::GAKUEN_KING:
-			text_w[i].reset(112, 310, 623, 391, false, false);
+			switch (i) {
+			default:
+			case 0: text_w[i].reset(112, 310, 623, 391, false, false); break;
+			case 1: text_w[i].reset(48, 310, 591, 391, false, false); break;
+			case 2: text_w[i].reset(0, 0, 639, 391, false, false); break;
+			case 3: text_w[i].reset(24, 310, 183, 391, false, false); break;
+			case 4: text_w[i].reset(464, 310, 623, 391, false, false); break;
+			}
 			menu_w[i].reset(416, 24, 591, 248, true, true);
 			break;
 		default:
@@ -325,4 +332,3 @@ void AGS::draw_window(int sx, int sy, int ex, int ey, bool frame, uint8 frame_co
 	}
 	draw_screen(sx, sy, ex - sx + 1, ey - sy + 1);
 }
-
diff --git a/src/sys/nact.h b/src/sys/nact.h
index cc159bb..766c18e 100644
--- a/src/sys/nact.h
+++ b/src/sys/nact.h
@@ -207,6 +207,56 @@ private:
 	static NACT* create_system3(const Config& config, const GameId& game_id);
 };
 
+class NACT_Sys3 : public NACT {
+public:
+	NACT_Sys3(const Config& config, const GameId& game_id) : NACT(config, game_id) {}
+	static NACT_Sys3* create(const Config& config, const GameId& game_id);
+
+protected:
+	void cmd_branch() override;
+	void cmd_open_verb() override;
+	void cmd_b() override;
+	void cmd_e() 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_t() override;
+	void cmd_u() override;
+	void cmd_v() override;
+	void cmd_w() override;
+	void cmd_y() override;
+	void cmd_z() override;
+	uint16 cali() override;
+
+	void exec_y(int cmd, int param);
+	uint16 cali2();
+
+private:
+	static constexpr int MAX_PCM = 256;
+
+	int pcm_index = 0;
+	int pcm[MAX_PCM] = {};
+	bool column = true;		// 座標モード
+	int mouse_sence = 16;	// マウス感度
+
+	void cmd_open_obj(int verb);
+	struct K3HackInfo;
+	static const K3HackInfo yakata3cd_k3_hack_table[];
+	static const K3HackInfo yakata3fd_k3_hack_table[];
+	static const K3HackInfo onlyyou_k3_hack_table[];
+	bool k3_hack(const K3HackInfo* info_table);
+};
+
+NACT_Sys3* create_gakuen_king(const Config& config, const GameId& game_id);
+
 extern std::unique_ptr<NACT> g_nact;
 
 #endif // _NACT_H_
diff --git a/src/sys/nact_gakuenking.cpp b/src/sys/nact_gakuenking.cpp
new file mode 100644
index 0000000..7a48fd3
--- /dev/null
+++ b/src/sys/nact_gakuenking.cpp
@@ -0,0 +1,179 @@
+#include <algorithm>
+#include "nact.h"
+#include "ags.h"
+#include "mako.h"
+
+namespace {
+
+class NACT_GakuenKing : public NACT_Sys3 {
+public:
+	NACT_GakuenKing(const Config& config, const GameId& game_id)
+		: NACT_Sys3(config, game_id) {}
+
+	void cmd_b() override {
+		int p1 = cali();
+		int p2 = cali();
+		TRACE_UNIMPLEMENTED("B %d,%d:", p1, p2);
+	}
+
+	void cmd_i() override {
+		int p1 = cali();
+		int p2 = cali();
+		int p3 = cali();
+
+		switch (p1) {
+		case 1:
+			if (p3 == 255) {
+				for (int i = 0; i < 63; i++) {
+					grid_select_data[i] = p2;
+				}
+			} else if (1 <= p3 && p3 <= 63) {
+				grid_select_data[p3 - 1] = p2;
+			}
+			break;
+		case 2:
+			switch (p2) {
+			case 1:
+				RND = grid_select(376, 8, 32, 32, 7, 9, grid_prev_selection);
+				if (RND != GRID_SELECT_CANCELED)
+					grid_prev_selection = RND;
+				wait_key_release();
+				break;
+			default:
+				TRACE_UNIMPLEMENTED("I %d,%d,%d:", p1, p2, p3);
+				return;
+			}
+			break;
+		default:
+			TRACE_UNIMPLEMENTED("I %d,%d,%d:", p1, p2, p3);
+			return;
+		}
+		TRACE("I %d,%d,%d:", p1, p2, p3);
+	}
+
+	void cmd_n() override {
+		int p1 = cali();
+		int p2 = cali();
+		TRACE_UNIMPLEMENTED("N %d,%d:", p1, p2);
+	}
+
+	void cmd_p() override {
+		int p1 = cali();
+		TRACE("P %d:", p1);
+		ags->text.font_color = p1;
+	}
+
+	void cmd_t() override {
+		int p1 = cali();
+		int p2 = cali();
+		int p3 = cali();
+		TRACE_UNIMPLEMENTED("T %d,%d,%d:", p1, p2, p3);
+	}
+
+	void cmd_w() override {
+		int p1 = cali();
+		int p2 = cali();
+		int p3 = cali();
+		TRACE_UNIMPLEMENTED("W %d,%d,%d:", p1, p2, p3);
+	}
+
+	void cmd_y() override {
+		int cmd = cali();
+		int param = cali();
+
+		TRACE("Y %d,%d:", cmd, param);
+
+		switch (cmd) {
+		case 14:
+		case 26:
+		case 80:
+		case 81:
+		case 82:
+			TRACE_UNIMPLEMENTED("Y %d,%d:", cmd, param);
+			break;
+		case 9:
+			for (int page = 1; page <= 99; page++)
+				mako->set_cd_track(page, param ? page : 0);
+			break;
+		case 20:  // audio device check
+			exec_y(14, param);
+			break;
+		case 25:
+			if (0 <= param && param <= 4) {
+				ags->menu.back_color = ags->text.back_color =
+					(param == 1 || param == 2) ? 0 : 1;
+				text_window = param + 1;
+				ags->open_text_window(text_window, false);
+			}
+			break;
+		case 83:
+			sco.label_stack_clear();
+			sco.page_stack_clear();
+			break;
+		case 118:
+			ags->text.pos.x = param;
+			break;
+		case 119:
+			ags->text.pos.y = param;
+			break;
+		default:
+			exec_y(cmd, param);
+			break;
+		}
+	}
+
+	void cmd_z() override {
+		int p1 = cali();
+		int p2 = cali();
+		int p3 = cali();
+		TRACE_UNIMPLEMENTED("Z %d,%d,%d:", p1, p2, p3);
+	}
+
+private:
+	const uint16_t GRID_SELECT_CANCELED = 80;
+	uint16_t grid_select_data[63] = {};
+	uint16_t grid_prev_selection = 0;
+
+	// I command
+	uint16_t grid_select(int left_x, int top_y, int xsize, int ysize, int nr_cols, int nr_rows, int initial_index) {
+		int x = initial_index % nr_cols;
+		int y = initial_index / nr_cols;
+		set_cursor(x * xsize + xsize / 2 + left_x, y * ysize + ysize / 2 + top_y);
+		while (!terminate) {
+			int mx, my;
+			get_cursor(&mx, &my);
+			x = (mx - left_x) / xsize;
+			y = (my - top_y) / ysize;
+			int key = get_key();
+			if (key & 0xf) {
+				if (key & 1) y--;  // up
+				if (key & 2) y++;  // down
+				if (key & 4) x--;  // left
+				if (key & 8) x++;  // right
+				x = std::clamp(x, 0, nr_cols - 1);
+				y = std::clamp(y, 0, nr_rows - 1);
+				set_cursor(x * xsize + xsize / 2 + left_x, y * ysize + ysize / 2 + top_y);
+				wait_key_release();
+			} else if (key == 16) {  // enter
+				wait_key_release();
+				if (0 <= x && x < nr_cols && 0 <= y && y < nr_rows) {
+					int sel = nr_cols * y + x;
+					if (grid_select_data[sel])
+						return sel + 1;
+				}
+			} else if (key == 32) {  // space
+				wait_key_release();
+				return GRID_SELECT_CANCELED;
+			} else {
+				sys_sleep(16);
+			}
+		}
+		return GRID_SELECT_CANCELED;
+	}
+};
+
+} // namespace
+
+NACT_Sys3* create_gakuen_king(const Config& config, const GameId& game_id) {
+	return new NACT_GakuenKing(config, game_id);
+}
diff --git a/src/sys/nact_sys3.cpp b/src/sys/nact_sys3.cpp
index 2d4ddcc..77a9436 100644
--- a/src/sys/nact_sys3.cpp
+++ b/src/sys/nact_sys3.cpp
@@ -75,56 +75,6 @@
 #define M_X var[57]
 #define M_Y var[58]
 
-#define MAX_PCM 256
-
-namespace {
-
-class NACT_Sys3 : public NACT {
-public:
-	NACT_Sys3(const Config& config, const GameId& game_id) : NACT(config, game_id) {}
-
-protected:
-	void cmd_branch() override;
-	void cmd_open_verb() override;
-	void cmd_b() override;
-	void cmd_e() 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_t() override;
-	void cmd_u() override;
-	void cmd_v() override;
-	void cmd_w() override;
-	void cmd_y() override;
-	void cmd_z() override;
-	uint16 cali() override;
-
-	void exec_y(int cmd, int param);
-
-private:
-	int pcm_index = 0;
-	int pcm[MAX_PCM] = {};
-	bool column = true;		// 座標モード
-	int mouse_sence = 16;	// マウス感度
-
-	void cmd_open_obj(int verb);
-	uint16 cali2();
-
-	struct K3HackInfo;
-	static const K3HackInfo yakata3cd_k3_hack_table[];
-	static const K3HackInfo yakata3fd_k3_hack_table[];
-	static const K3HackInfo onlyyou_k3_hack_table[];
-	bool k3_hack(const K3HackInfo* info_table);
-};
-
 void NACT_Sys3::cmd_branch()
 {
 	int condition = cali();
@@ -1314,6 +1264,8 @@ bool NACT_Sys3::k3_hack(const K3HackInfo* info_table)
 	return true;
 }
 
+namespace {
+
 class NACT_Toushin2 : public NACT_Sys3 {
 public:
 	NACT_Toushin2(const Config& config, const GameId& game_id)
@@ -1359,126 +1311,22 @@ public:
 	}
 };
 
-class NACT_GakuenKing : public NACT_Toushin2 {
-public:
-	NACT_GakuenKing(const Config& config, const GameId& game_id)
-		: NACT_Toushin2(config, game_id) {}
-
-	void cmd_i() override {
-		int p1 = cali();
-		int p2 = cali();
-		int p3 = cali();
-
-		switch (p1) {
-		case 1:
-			if (p3 == 255) {
-				for (int i = 0; i < 63; i++) {
-					grid_select_data[i] = p2;
-				}
-			} else if (1 <= p3 && p3 <= 63) {
-				grid_select_data[p3 - 1] = p2;
-			}
-			break;
-		case 2:
-			switch (p2) {
-			case 1:
-				RND = grid_select(376, 8, 32, 32, 7, 9, grid_prev_selection);
-				if (RND != GRID_SELECT_CANCELED)
-					grid_prev_selection = RND;
-				wait_key_release();
-				break;
-			default:
-				TRACE_UNIMPLEMENTED("I %d,%d,%d:", p1, p2, p3);
-				return;
-			}
-			break;
-		default:
-			TRACE_UNIMPLEMENTED("I %d,%d,%d:", p1, p2, p3);
-			return;
-		}
-		TRACE("I %d,%d,%d:", p1, p2, p3);
-	}
-
-	void cmd_y() override {
-		int cmd = cali();
-		int param = cali();
-
-		TRACE("Y %d,%d:", cmd, param);
-
-		switch (cmd) {
-		case 20:  // audio device check
-			exec_y(14, param);
-			break;
-		case 25:
-			ags->menu.back_color = ags->text.back_color = (param == 1 || param == 2) ? 0 : 1;
-			// text_window = param;
-			break;
-		case 118:
-			ags->text.pos.x = param;
-			break;
-		case 119:
-			ags->text.pos.y = param;
-			break;
-		default:
-			exec_y(cmd, param);
-			break;
-		}
-	}
-
-private:
-	const uint16_t GRID_SELECT_CANCELED = 80;
-	uint16_t grid_select_data[63] = {};
-	uint16_t grid_prev_selection = 0;
-
-	// I command
-	uint16_t grid_select(int left_x, int top_y, int xsize, int ysize, int nr_cols, int nr_rows, int initial_index) {
-		int x = initial_index % nr_cols;
-		int y = initial_index / nr_cols;
-		set_cursor(x * xsize + xsize / 2 + left_x, y * ysize + ysize / 2 + top_y);
-		while (!terminate) {
-			int mx, my;
-			get_cursor(&mx, &my);
-			x = (mx - left_x) / xsize;
-			y = (my - top_y) / ysize;
-			int key = get_key();
-			if (key & 0xf) {
-				if (key & 1) y--;  // up
-				if (key & 2) y++;  // down
-				if (key & 4) x--;  // left
-				if (key & 8) x++;  // right
-				x = std::clamp(x, 0, nr_cols - 1);
-				y = std::clamp(y, 0, nr_rows - 1);
-				set_cursor(x * xsize + xsize / 2 + left_x, y * ysize + ysize / 2 + top_y);
-				wait_key_release();
-			} else if (key == 16) {  // enter
-				wait_key_release();
-				if (0 <= x && x < nr_cols && 0 <= y && y < nr_rows) {
-					int sel = nr_cols * y + x;
-					if (grid_select_data[sel])
-						return sel + 1;
-				}
-			} else if (key == 32) {  // space
-				wait_key_release();
-				return GRID_SELECT_CANCELED;
-			} else {
-				sys_sleep(16);
-			}
-		}
-		return GRID_SELECT_CANCELED;
-	}
-};
-
 }  // namespace
 
 // static
-NACT* NACT::create_system3(const Config& config, const GameId& game_id) {
+NACT_Sys3* NACT_Sys3::create(const Config& config, const GameId& game_id) {
 	switch (game_id.game) {
 	case GameId::TOUSHIN2:
 	case GameId::NISE_NAGURI:
 		return new NACT_Toushin2(config, game_id);
 	case GameId::GAKUEN_KING:
-		return new NACT_GakuenKing(config, game_id);
+		return create_gakuen_king(config, game_id);
 	default:
 		return new NACT_Sys3(config, game_id);
 	}
 }
+
+// static
+NACT* NACT::create_system3(const Config& config, const GameId& game_id) {
+	return NACT_Sys3::create(config, game_id);
+}