diff --git a/keyboards/cool836a/config.h b/keyboards/cool836a/config.h
new file mode 100644
index 00000000000..3ac036786fd
--- /dev/null
+++ b/keyboards/cool836a/config.h
@@ -0,0 +1,153 @@
+/*
+Copyright 2021 Ohashi
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see .
+*/
+
+#pragma once
+
+#include "config_common.h"
+
+/* USB Device descriptor parameter */
+#define VENDOR_ID 0xFEED
+#define PRODUCT_ID 0x0000
+#define DEVICE_VER 0x0001
+#define MANUFACTURER Ohashi
+#define PRODUCT cool836A
+
+/* key matrix size */
+#define MATRIX_ROWS 6
+#define MATRIX_COLS 6
+
+/*
+ * Keyboard Matrix Assignments
+ *
+ * Change this to how you wired your keyboard
+ * COLS: AVR pins used for columns, left to right
+ * ROWS: AVR pins used for rows, top to bottom
+ * DIODE_DIRECTION: COL2ROW = COL = Anode (+), ROW = Cathode (-, marked on diode)
+ * ROW2COL = ROW = Anode (+), COL = Cathode (-, marked on diode)
+ *
+ */
+#define MATRIX_ROW_PINS { D1, B5, B4, F4, B1, B6 }
+#define MATRIX_COL_PINS { F5, D0, B2, C6, D7, E6 }
+#define UNUSED_PINS
+
+/* COL2ROW, ROW2COL */
+//#define DIODE_DIRECTION COL2ROW
+#define DIODE_DIRECTION ROW2COL
+
+/*
+ * Split Keyboard specific options, make sure you have 'SPLIT_KEYBOARD = yes' in your rules.mk, and define SOFT_SERIAL_PIN.
+ */
+#define SOFT_SERIAL_PIN D0 // or D1, D2, D3, E6
+
+//#define LED_NUM_LOCK_PIN B0
+//#define LED_CAPS_LOCK_PIN B1
+//#define LED_SCROLL_LOCK_PIN B2
+//#define LED_COMPOSE_PIN B3
+//#define LED_KANA_PIN B4
+
+//#define BACKLIGHT_PIN B7
+//#define BACKLIGHT_LEVELS 3
+//#define BACKLIGHT_BREATHING
+
+//#define RGB_DI_PIN E2
+//#ifdef RGB_DI_PIN
+//# define RGBLED_NUM 16
+//# define RGBLIGHT_HUE_STEP 8
+//# define RGBLIGHT_SAT_STEP 8
+//# define RGBLIGHT_VAL_STEP 8
+//# define RGBLIGHT_LIMIT_VAL 255 /* The maximum brightness level */
+//# define RGBLIGHT_SLEEP /* If defined, the RGB lighting will be switched off when the host goes to sleep */
+/*== all animations enable ==*/
+//# define RGBLIGHT_ANIMATIONS
+/*== or choose animations ==*/
+//# define RGBLIGHT_EFFECT_BREATHING
+//# define RGBLIGHT_EFFECT_RAINBOW_MOOD
+//# define RGBLIGHT_EFFECT_RAINBOW_SWIRL
+//# define RGBLIGHT_EFFECT_SNAKE
+//# define RGBLIGHT_EFFECT_KNIGHT
+//# define RGBLIGHT_EFFECT_CHRISTMAS
+//# define RGBLIGHT_EFFECT_STATIC_GRADIENT
+//# define RGBLIGHT_EFFECT_RGB_TEST
+//# define RGBLIGHT_EFFECT_ALTERNATING
+/*== customize breathing effect ==*/
+/*==== (DEFAULT) use fixed table instead of exp() and sin() ====*/
+//# define RGBLIGHT_BREATHE_TABLE_SIZE 256 // 256(default) or 128 or 64
+/*==== use exp() and sin() ====*/
+//# define RGBLIGHT_EFFECT_BREATHE_CENTER 1.85 // 1 to 2.7
+//# define RGBLIGHT_EFFECT_BREATHE_MAX 255 // 0 to 255
+//#endif
+
+/* Debounce reduces chatter (unintended double-presses) - set 0 if debouncing is not needed */
+#define DEBOUNCE 5
+
+/* define if matrix has ghost (lacks anti-ghosting diodes) */
+//#define MATRIX_HAS_GHOST
+
+/* Mechanical locking support. Use KC_LCAP, KC_LNUM or KC_LSCR instead in keymap */
+#define LOCKING_SUPPORT_ENABLE
+/* Locking resynchronize hack */
+#define LOCKING_RESYNC_ENABLE
+
+/* If defined, GRAVE_ESC will always act as ESC when CTRL is held.
+ * This is useful for the Windows task manager shortcut (ctrl+shift+esc).
+ */
+//#define GRAVE_ESC_CTRL_OVERRIDE
+
+/*
+ * Force NKRO
+ *
+ * Force NKRO (nKey Rollover) to be enabled by default, regardless of the saved
+ * state in the bootmagic EEPROM settings. (Note that NKRO must be enabled in the
+ * makefile for this to work.)
+ *
+ * If forced on, NKRO can be disabled via magic key (default = LShift+RShift+N)
+ * until the next keyboard reset.
+ *
+ * NKRO may prevent your keystrokes from being detected in the BIOS, but it is
+ * fully operational during normal computer usage.
+ *
+ * For a less heavy-handed approach, enable NKRO via magic key (LShift+RShift+N)
+ * or via bootmagic (hold SPACE+N while plugging in the keyboard). Once set by
+ * bootmagic, NKRO mode will always be enabled until it is toggled again during a
+ * power-up.
+ *
+ */
+//#define FORCE_NKRO
+
+/*
+ * Feature disable options
+ * These options are also useful to firmware size reduction.
+ */
+
+/* disable debug print */
+//#define NO_DEBUG
+
+/* disable print */
+//#define NO_PRINT
+
+/* disable action features */
+//#define NO_ACTION_LAYER
+//#define NO_ACTION_TAPPING
+//#define NO_ACTION_ONESHOT
+
+/* disable these deprecated features by default */
+#define NO_ACTION_MACRO
+#define NO_ACTION_FUNCTION
+
+/* Bootmagic Lite key configuration */
+//#define BOOTMAGIC_LITE_ROW 0
+//#define BOOTMAGIC_LITE_COLUMN 0
diff --git a/keyboards/cool836a/cool836a.c b/keyboards/cool836a/cool836a.c
new file mode 100644
index 00000000000..5795bf9546c
--- /dev/null
+++ b/keyboards/cool836a/cool836a.c
@@ -0,0 +1,17 @@
+/* Copyright 2021 Ohashi
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+#include "cool836a.h"
diff --git a/keyboards/cool836a/cool836a.h b/keyboards/cool836a/cool836a.h
new file mode 100644
index 00000000000..08a036d4c01
--- /dev/null
+++ b/keyboards/cool836a/cool836a.h
@@ -0,0 +1,42 @@
+/* Copyright 2021 Ohashi
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see .
+ */
+
+#pragma once
+
+#include "quantum.h"
+
+/* This is a shortcut to help you visually see your layout.
+ *
+ * The first section contains all of the arguments representing the physical
+ * layout of the board and position of the keys.
+ *
+ * The second converts the arguments into a two-dimensional array which
+ * represents the switch matrix.
+ */
+
+#define LAYOUT( \
+ K000, K001, K002, K003, K004, K005, K300, K301, K302, K303, K304, K305, \
+ K100, K101, K102, K103, K104, K105, K400, K401, K402, K403, K404, K405, \
+ K200, K201, K202, K203, K204, K205, K500, K501, K502, K503, K504, K505 \
+) \
+{ \
+ { K000, K001, K002, K003, K004, K005 }, \
+ { K100, K101, K102, K103, K104, K105 }, \
+ { K200, K201, K202, K203, K204, K205 }, \
+ { K300, K301, K302, K303, K304, K305 }, \
+ { K400, K401, K402, K403, K404, K405 }, \
+ { K500, K501, K502, K503, K504, K505 }, \
+}
diff --git a/keyboards/cool836a/info.json b/keyboards/cool836a/info.json
new file mode 100644
index 00000000000..01f99649075
--- /dev/null
+++ b/keyboards/cool836a/info.json
@@ -0,0 +1,19 @@
+{
+ "keyboard_name": "cool836a",
+ "url": "https://github.com/telzo2000/cool836A",
+ "maintainer": "Ohashi",
+ "width": 12,
+ "height": 3,
+ "layouts": {
+ "LAYOUT": {
+ "layout": [
+ {"x": 0, "y": 0},{"x": 1, "y": 0},{"x": 2, "y": 0},{"x": 3, "y": 0},{"x": 4, "y": 0},{"x": 5, "y": 0},
+ {"x": 7.5, "y": 0},{"x": 8.5, "y": 0},{"x": 9.5, "y": 0},{"x": 10.5, "y": 0},{"x": 11.5,"y": 0},{"x": 12.5,"y": 0},
+ {"x": 0, "y": 1},{"x": 1.5, "y": 1},{"x": 2.5, "y": 1},{"x": 3.5, "y": 1},{"x": 4.5, "y": 1},{"x": 5.5, "y": 1},
+ {"x": 8, "y": 1},{"x": 9, "y": 1},{"x": 10, "y": 1},{"x": 11, "y": 1},{"x": 12,"y": 1},{"x": 13,"y": 1},
+ {"x": 0, "y": 2},{"x": 2, "y": 2},{"x": 3, "y": 2},{"x": 4, "y": 2},{"x": 5, "y": 2},{"x": 6, "y": 2},
+ {"x": 7.5, "y": 2},{"x": 8.5, "y": 2},{"x": 9.5, "y": 2},{"x": 10.5, "y": 2},{"x": 11.5,"y": 2},{"x": 12.5,"y": 2}
+ ]
+ }
+ }
+}
diff --git a/keyboards/cool836a/keymaps/default/keymap.c b/keyboards/cool836a/keymaps/default/keymap.c
new file mode 100644
index 00000000000..458cfba85ea
--- /dev/null
+++ b/keyboards/cool836a/keymaps/default/keymap.c
@@ -0,0 +1,41 @@
+/* Copyright 2021 Ohashi
+*
+* This program is free software: you can redistribute it and/or modify
+* it under the terms of the GNU General Public License as published by
+* the Free Software Foundation, either version 2 of the License, or
+* (at your option) any later version.
+*
+* This program is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+* GNU General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License
+* along with this program. If not, see .
+*/
+
+#include QMK_KEYBOARD_H
+
+const uint16_t PROGMEM keymaps[][MATRIX_ROWS][MATRIX_COLS] = {
+ /* Base */
+ [0] = LAYOUT(
+ KC_ESC, LALT_T(KC_Q), KC_W, KC_E, KC_R, KC_T, KC_Y, KC_U, KC_I, KC_O, KC_P, KC_BSPC,
+ KC_LCTL, KC_A, KC_S, KC_D, KC_F, KC_G, KC_H, KC_J, KC_K, KC_L, KC_MINS, KC_ENTER,
+ KC_LSFT, KC_Z, GUI_T(KC_X), KC_C, LT(3, KC_V), LT(2, KC_B), KC_SPC, LT(1, KC_N), KC_M, KC_COMM, KC_DOT, KC_SPC
+ ),
+ [1] = LAYOUT(
+ KC_TAB, KC_1, KC_2, KC_3, KC_4, KC_5, KC_6, KC_7, KC_8, KC_9, KC_0, KC_BSPC,
+ KC_LCTL, KC_EXLM, KC_AT, KC_HASH, KC_DLR, KC_PERC, KC_PLUS, KC_MINS, KC_ASTR, KC_PSLS, KC_EQL, KC_ENTER,
+ KC_LSFT, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_SPC
+ ),
+ [2] = LAYOUT(
+ KC_TAB, KC_F1, KC_F2, KC_F3, KC_F4, KC_F5, KC_F6, KC_F7, KC_F8, KC_F9, KC_F10, KC_BSPC,
+ KC_LCTL, KC_LBRC, KC_RBRC, KC_BSLS, KC_SCLN, KC_COLN, KC_LEFT, KC_DOWN, KC_UP, KC_RIGHT, KC_QUES, KC_ENTER,
+ KC_LSFT, KC_UNDS, KC_PIPE, KC_CIRC, KC_TILD, _______, _______, _______, _______, _______, _______, KC_SPC
+ ),
+ [3] = LAYOUT(
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, KC_LPRN, KC_RPRN, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______,
+ _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______
+ )
+};
diff --git a/keyboards/cool836a/keymaps/default/readme.md b/keyboards/cool836a/keymaps/default/readme.md
new file mode 100644
index 00000000000..05a5d7fe36b
--- /dev/null
+++ b/keyboards/cool836a/keymaps/default/readme.md
@@ -0,0 +1,15 @@
+# m.ki様によるデフォルトキーマップ
+
+[レッドバージョン ビルドガイド](https://github.com/telzo2000/cool836A/blob/master/buildguide_red.md)で紹介されていたキーマップです。チートシートを見ながらコードに書き写しました。
+
+-------
+## チートシート
+以下、[同ページ](https://github.com/telzo2000/cool836A/blob/master/buildguide_red.md)の画像のコピーを添付します。
++ Layer=0
+![Layer=0](https://github.com/oha-Ohashi/qmk_firmware/blob/images/default_keymap/default_0.png)
++ Layer=1
+![Layer=1](https://github.com/oha-Ohashi/qmk_firmware/blob/images/default_keymap/default_1.png)
++ Layer=2
+![Layer=2](https://github.com/oha-Ohashi/qmk_firmware/blob/images/default_keymap/default_2.png)
++ Layer=3
+![Layer=3](https://github.com/oha-Ohashi/qmk_firmware/blob/images/default_keymap/default_3.png)
diff --git a/keyboards/cool836a/readme.md b/keyboards/cool836a/readme.md
new file mode 100644
index 00000000000..dd3ace3cbc3
--- /dev/null
+++ b/keyboards/cool836a/readme.md
@@ -0,0 +1,51 @@
+# cool836A
+
+- このプロジェクトの詳細については設計者たる[m.ki様](https://twitter.com/0002ozlet)による[GitHubリポジトリ](https://github.com/telzo2000/cool836A)の記述をご覧ください。
+
+### バージョン(A, B+, C+)について
+- m.ki様によるとどのバージョンも回路は同じで、ファームウェアを分ける必要はないとのことです。
+- しかしながらこのファームウェアは、cool836A ver.B+ (通称レッドバージョン)のみでテストされています(2021年1月7日現在)。そのため念のため、当面の間はサブフォルダの名前をcool836A/verB_REDとさせていただきます。
+- ほかのバージョンに書き込んだときに不具合等がありましたら、方はお気軽に私[オオハシ](https://twitter.com/oha_oha_Ohashi)までご連絡ください。
+
+
+## 申し訳程度のチュートリアル
+詳細に書き込む労力は払えませんでしたが、最低限のコードのみ記します。
+
+git clone のあと、
+
+``` make cool836A/verB_RED:default ```
+
+でコンパイル可能であることを確認し、
+
+``` make cool836A/verB_RED:default:avrdude ```
+
+によってデフォルトキーマップをPro Microに焼けるかもしれません。
+`default`の代わりに`Ohasheen`を利用することもできます。
+
+初心者の方はもっと素晴らしいウェブサイトでGitやqmk firmwareの使い方を覚えていただくのがよいかと思います。
+
+
+
+-----------------
+## English
+- [Here](https://github.com/telzo2000/cool836A) are a full description of this project and build guide by the great Designer: [m.ki](imgur.com image replace me!)
+
+- Each virsions(A, B+, C+) of cool836A has the same circuit and that means you can install this firmware on any of them.
+- However, this repository is currently(Jan 7, 2021) tested on ver.B+ (RED version) only. Feel free to contact [ME](https://github.com/ketcha-k) for any problems.
+
+- firmware maintainer: [Ohashi](https://github.com/ketcha-k)
+
+## Such a humble tutorial
+The author would like to provide a minimum guide.
+
+After cloning the repository, you may want to
+
+``` make cool836A/verB_RED ```
+
+to make sure it's compilable, and
+
+``` make cool836A/verB_RED:default ```
+
+which leads you to the goal.
+
+It is recommended that beginners learn how to get started with qmk firmware/configurator at other fantastic websites rather than here......
diff --git a/keyboards/cool836a/rules.mk b/keyboards/cool836a/rules.mk
new file mode 100644
index 00000000000..5c0d8f307c5
--- /dev/null
+++ b/keyboards/cool836a/rules.mk
@@ -0,0 +1,22 @@
+# MCU name
+MCU = atmega32u4
+
+# Bootloader selection
+BOOTLOADER = atmel-dfu
+
+# Build Options
+# change yes to no to disable
+#
+BOOTMAGIC_ENABLE = lite # Virtual DIP switch configuration
+MOUSEKEY_ENABLE = yes # Mouse keys
+EXTRAKEY_ENABLE = yes # Audio control and System control
+CONSOLE_ENABLE = no # Console for debug
+COMMAND_ENABLE = no # Commands for debug and configuration
+# Do not enable SLEEP_LED_ENABLE. it uses the same timer as BACKLIGHT_ENABLE
+SLEEP_LED_ENABLE = no # Breathing sleep LED during USB suspend
+# if this doesn't work, see here: https://github.com/tmk/tmk_keyboard/wiki/FAQ#nkro-doesnt-work
+NKRO_ENABLE = no # USB Nkey Rollover
+BACKLIGHT_ENABLE = no # Enable keyboard backlight functionality
+RGBLIGHT_ENABLE = no # Enable keyboard RGB underglow
+BLUETOOTH_ENABLE = no # Enable Bluetooth
+AUDIO_ENABLE = no # Audio output