Detective Conan: Case Closed! A5 Cousin Size - Techo Lineup

Detective ConanCase Closed!A5 Cousin Size

2026 New
ON SALE FEB 1
JAPAN ONLY

This product is available for shipment within Japan only.
International shipping is not available.

This collaboration brings the world of Detective Conan, the popular mystery manga serialized in Weekly Shonen Sunday, to the Hobonichi Techo.

Write down the day’s events, and the moment you fasten the cover’s button... “Case Closed!” Designed with a classical look inspired by the British detective attire that Conan admires, this cover is ready for your cases, romance, and memories. It’s a “Life Book” just for you, to spend every day with.

The cover is a trifold type that closes with a snap button. It features a retro British-style plaid pattern and a commemorative name tag logo representing the collaboration between Detective Conan and the Hobonichi Techo.

The pen hook inside the cover is designed to hold a pen by its clip.

Inside the cover, numerous famous scenes selected from Detective Conan are lined up. The two bookmarks come in blue and red, inspired by Conan’s jacket and bow tie.

There are even more original illustrations hidden in the sleeves where you insert the techo book. Be sure to take a peek to see what pictures are inside.

We also created a pocket featuring the familiar keyhole motif found on the back covers of the comics. If you insert your favorite card or photo, its face will peek out through the keyhole.

The pocket features a quote that appears frequently in the original work, stamped in gold foil: “When you have eliminated the impossible, whatever remains, however improbable, must be the truth.”

The Detective Conan lineup includes not only the techo but also stationery and accessories suitable for various scenes. Why not carry famous scenes from Detective Conan with you on items designed for daily use?

© Gosho Aoyama/Shogakukan

Staff List

Photographer: Styled Images: Nobuki Kawaharazaki / Product Detail: Hiroyuki Oe
Stylist: Haruka Kimura

Detective ConanCase Closed!A5 Cousin Size

¥12,320 - ¥13,970 (incl. tax)
¥8,800 (incl. tax)

20 per item

Unavailable

Normal

Specifications*Specifications may vary slightly

Cover

Size

H: 228 x W: 444 x T: 3 mm / H: 9" x W: 17.5" x T: 0.1"

Weight

Approx. 227 g

Main material

Exterior: Polyester, Polyurethane / Interior: PU, Polyester

Compatible Techo Books

Cousin (A5)
1 page per day
Cousin Avec (A5)
1 page per day 6-month book
Day-Free
Monthly notebook

Cousin | One-Page-Per-Day TypeJapanese / English

type	Monday Start (Japanese) Monday Start (English)
Size	A5 H: 210 x W: 148 x T: 18 mm / H: 8.3" x W: 5.8" x T: 0.7" *Specifications may vary slightly
Weight	Approx. 445 g
Dates	Jan 2026 - Dec 2026 (Jan start) Apr 2026 - Mar 2027 (Apr start)

A daily techo with lots of space to write

This A5-size techo provides ample space on each daily page. It’s great for keeping in one place at home or at work and you can use it to track your child’s growth or exchange with someone.

Daily pages
Yearly calendar
Yearly index
Monthly calendar
Weekly pages
Memo pages

View details on features and included content

Cousin Avec | One-Page-Per-Day Type (2-Book Set)Japanese

type	Monday Start (Japanese)
Size	A5 Each Book: H: 210 x W: 148 x T: 10 mm / H: 8.3" x W: 5.8" x T: 0.4" *Specifications may vary slightly
Weight	Each Book: Approx. 260 g
Dates	Book 1: Jan 2026 - June 2026 Book 2: July 2026 - Dec 2026

Each 6-month daily techo is thin and light for easy carry

This techo splits the year into two 6-month books, making it easy to carry while keeping the same page design and layout as the standard edition.

Daily pages
Yearly calendar
Yearly index
Monthly calendar
Weekly pages
Memo pages

View details on features and included content

Day-Free | Monthly Techo + NotebookJapanese

type	Monday Start (Japanese)
Size	A5 H: 210 x W: 148 x T: 8 mm / H: 8.3" x W: 5.8" x T: 0.3" *Specifications may vary slightly
Weight	Approx. 220 g
Dates	Dec 2025 - Mar 2027

A monthly notebook with undated pages to write freely

This techo starts with monthly calendars and ends with undated graph paper pages so you can write whenever you want, and as much as you want.

Monthly calendar
Yearly calendar
Yearly index
Graph paper notebook pages

View details on features and included content

Book (Cousin Japanese Edition / Japanese / April Start)

Size	A5 size H: 210 x W: 148 x T: 18 mm / H: 8.3" x W: 5.8" x T: 0.7" *Actual book size may vary slightly
Weight	Approx. 445 g
Language	Japanese
Pages	544 pages
Paper Type / Binding	Thin, light Tomoe River paper that is smooth to write on and designed for planners / Stitch-binding
Graph Paper Size	3.7 mm
Start of Week	Monday-start week
Yearly Calendar	2025, 2026, 2027
Yearly Index	Apr. 2026 - Mar. 2027 (4 pages)
Monthly Calendar	Feb. 2026 - May 2027 (32 pages)
Daily Pages	Apr. 1, 2026 - Mar. 31, 2027 (377 pages) A page is included at the beginning of each month to help in planning ahead. All daily pages include daily quotes. Includes a mini monthly calendar at the bottom right of every two-page spread (Monday-start). Additionally, 3 blank pages are featured at the beginning to provide a free area when starting out the book.
Daily Quotes	One per day (Japanese)
Weekly Pages	Mar. 30, 2026 - Apr. 4, 2027 (106 pages)
Memo Pages	4 pages
Bonus Pages	Time Table / Graph Paper / Favorites / My 100 / Memories 2026 / 12 Switches to Help You Focus / For a Comfortable Night’s Sleep / Solar Terms / Emergency Preparedness / Gifts / Age Table / Conversion Chart / Getting the most of Hobonichi / Addresses / Personal Notes
Listed Information	Day of the year / Week of the year (listed on monthly calendars and weekly pages) / Old lunar calendar / Rokuyo (traditional Japanese lunisolar calendar) (listed on monthly calendars) / Solar terms / Japanese holidays / Moon phase (daily pages include every phase, monthly calendars and weekly pages only include full and new moon)
Other	See the Exploring Each Type page for more details

Book (Cousin English Edition / English / January Start)

Size	A5 size H: 210 x W: 148 x T: 18 mm / H: 8.3" x W: 5.8" x T: 0.7" *Actual book size may vary slightly
Weight	Approx. 445 g
Language	English
Pages	544 pages
Paper Type / Binding	Thin, light Tomoe River paper that is smooth to write on and designed for planners / Stitch-binding
Graph Paper Size	3.7 mm
Start of Week	Monday-start week
Yearly Calendar	2025, 2026, 2027
Yearly Index	Jan. 2026 - Dec 2026 (4 pages)
Monthly Calendar	Dec. 2025 - Mar. 2027 (32 pages)
Daily Pages	Jan. 1 - Dec. 31, 2026 (377 pages) A page is included at the beginning of each month to help in planning ahead. Every two-page spread includes one daily quote. Includes a mini monthly calendar at the bottom right of every two-page spread (Monday-start). Additionally, a blank two-page spread is featured at the beginning to provide a free area when starting out the book.
Daily Quotes	One quote per two-page spread (English)
Weekly Pages	Dec 29, 2025 - Jan 3, 2027 (106 pages)
Memo Pages	6 pages
Bonus Pages	Time Table / Graph Paper / Favorites / My 100 / Memories 2026 / 12 Switches to Help You Focus / For a Comfortable Night’s Sleep / Words to Remember / 365 Days Check-Off Sheet / Getting the Most Out of Your Hobonichi Techo / Gifts / Addresses / Personal Notes
Listed Information	Day of the year / Week of the year (listed on monthly calendars and weekly pages) / Moon phase (daily pages include every phase, monthly calendars and weekly pages only include full and new moon)
Other	See the Exploring Each Type page for more details

Book (Cousin / Japanese / January Start)

Size	A5 size H: 210 x W: 148 x T: 18 mm / H: 8.3" x W: 5.8" x T: 0.7" *Actual book size may vary slightly
Weight	Approx. 445 g
Language	Japanese
Pages	544 pages
Paper Type / Binding	Thin, light Tomoe River paper that is smooth to write on and designed for planners / Stitch-binding
Graph Paper Size	3.7 mm
Start of Week	Monday-start week
Yearly Calendar	2025, 2026, 2027
Yearly Index	Jan. 2026 - Dec 2026 (4 pages)
Monthly Calendar	Dec. 2025 - Mar. 2027 (32 pages)
Daily Pages	Jan. 1 - Dec. 31, 2026 (377 pages) A page is included at the beginning of each month to help in planning ahead. All daily pages include daily quotes. Includes a mini monthly calendar at the bottom right of every two-page spread (Monday-start). Additionally, a blank two-page spread is featured at the beginning to provide a free area when starting out the book.
Daily Quotes	One per day (Japanese)
Weekly Pages	Dec 29, 2025 - Jan 3, 2027 (106 pages)
Memo Pages	6 pages
Bonus Pages	Time Table / Graph Paper / Favorites / My 100 / Memories 2026 / 12 Switches to Help You Focus / For a Comfortable Night’s Sleep / Solar Terms / Emergency Preparedness / Gifts / Age Table / Conversion Chart / Getting the most of Hobonichi / Addresses / Personal Notes
Listed Information	Day of the year / Week of the year (listed on monthly calendars and weekly pages) / Old lunar calendar / Rokuyo (traditional Japanese lunisolar calendar) (listed on monthly calendars) / Solar terms / Japanese holidays / Moon phase (daily pages include every phase, monthly calendars and weekly pages only include full and new moon)
Other	See the Exploring Each Type page for more details

Book (Cousin Avec / Japanese / January Start / 2-Book Set)

Size	A5 size x 2 books Each Book: H: 210 x W: 148 x T: 10 mm / H: 8.3" x W: 5.8" x T: 0.4" *Actual book size may vary slightly
Weight	Each Book: Approx. 260 g
Language	Japanese
Pages	Each Book: 288 pages
Paper Type / Binding	Thin, light Tomoe River paper that is smooth to write on and designed for planners / Stitch-binding
Start of Week	3.7 mm
Start of Week	Monday-start week
Yearly Calendar	2025, 2026, 2027
Yearly Index	Book 1: Jan. - Dec. 2026 (4 pages) Book 2: Jul. 2026 - Jun. 2027 (4 pages)
Monthly Calendar	Book 1: Dec. 2025 - Jul. 2026 (16 pages) Book 2: Jun. 2026 - Jan. 2027 (16 pages)
Daily Pages	Book 1: Jan. 1 - Jun. 30, 2026 (187 pages) Book 2: Jul. 1 - Dec. 31, 2026 (190 pages) A page is included at the beginning of each month to help in planning ahead. All daily pages include daily quotes. Includes a mini monthly calendar at the bottom right of every two-page spread (Monday-start). Additionally, a blank two-page spread (three pages for Book 2) is featured at the beginning to provide a free area when starting out the book.
Daily Quotes	One per day (Japanese)
Weekly Pages	Book 1: Dec. 29, 2025 - Jul. 5, 2026 (54 pages) Book 2: Jun. 29, 2026 - Jan. 3, 2027 (54 pages)
Memo Pages	Book 1: 8 pages Book 2: 4 pages
Bonus Pages	Time Table / Graph Paper / Favorites / My 100 / Memories 2026 / 12 Switches to Help You Focus / For a Comfortable Night’s Sleep / Solar Terms / Emergency Preparedness / Gifts / Age Table / Conversion Chart / Getting the most of Hobonichi / Addresses / Personal Notes
Listed Information	Day of the year / Week of the year (listed on monthly calendars and weekly pages) / Old lunar calendar / Rokuyo (traditional Japanese lunisolar calendar) (listed on monthly calendars) / Solar terms / Japanese holidays / Moon phase (daily pages include every phase, monthly calendars and weekly pages only include full and new moon)
Other	See the Exploring Each Type page for more details

Book (Day-Free A5 size / Japanese / Monthly)

Size	A5 size H: 210 x W: 148 x T: 8 mm / H: 8.3" x W: 5.8" x T: 0.3" *Actual book size may vary slightly
Weight	Approx. 220 g
Language	Japanese
Pages	224 pages
Paper Type / Binding	Thin, light Tomoe River paper that is smooth to write on and designed for planners / Stitch-binding
Graph Paper Size	3.7 mm
Start of Week	Monday-start week
Yearly Calendar	2025, 2026, 2027
Yearly Index	Jan. - Dec. 2025 (4 pages)
Monthly Calendar	Dec. 2025 - Mar. 2027 (32 pages)
Daily Quotes	Included (Japanese)
Graph Paper	171 pages
Bonus Pages	Time Table / Graph Paper / Favorites / My 100 / Memories 2026 / 12 Switches to Help You Focus / For a Comfortable Night’s Sleep / Solar Terms / Emergency Preparedness / Gifts / Age Table / Conversion Chart / Getting the most of Hobonichi / Addresses / Personal Notes
Listed Information	Day of the year / Week of the year (listed on monthly calendars) / Old lunar calendar / Rokuyo (traditional Japanese lunisolar calendar) (listed on monthly calendars) / Solar terms / Japanese holidays / Moon phase (Full and new moon listed on monthly calendars)
Other	See the Exploring Each Type page for more details

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Please Read Before You Buy

We’ve compiled a list of warnings, potential issues, and tips to keep in mind for this particular product. Additionally, the color of the product may be slightly different in actuality than compared to how it appeared on a computer or smartphone screen.