Manga-Based Extensive English Reading App "Langaku" and AI English Coach "ELSA" Jointly Develop English Learning Program for Schools

"Absorb a massive amount of English input through your favorite manga before you know it during summer vacation." Combining the joy of reading with AI pronunciation coaching to bring a new learning experience to schools that makes students "want to read and speak English aloud."


Mantra Inc. (Headquarters: Bunkyo-ku, Tokyo; CEO: Shonosuke Ishiwatari), operator of the manga-based extensive English reading app "Langaku," and ELSA Japan LLC (Headquarters: Shibuya-ku, Tokyo; Representative: Dai Imao), provider of the AI English speech support service "ELSA," are pleased to announce the joint development of an English learning program for schools. This program combines their respective strengths: "extensive English reading through manga" and "AI-powered pronunciation and speaking coaching."

This program is designed for summer vacation—a period when students can easily learn at their own pace. It allows them to absorb rich English input through their favorite manga, and then transition those lines into pronunciation and speaking practice with AI feedback. Both companies aim to increase the time students spend engaging with English while having fun, delivering a new learning experience to schools that bridges the gap between "being able to read" and "wanting to say it."

■ Background of Joint Development and Program Value

The importance of "input"—engaging with a massive amount of English within context—is widely recognized as the foundation for improving English proficiency. However, for many students, continuously reading large amounts of English in textbooks or long-form comprehension passages poses a high psychological barrier, making voluntary continuity difficult.

"Langaku" solves this problem through the power of manga, a highly approachable medium. Featuring over 100 popular manga titles such as ONE PIECE and Demon Slayer: Kimetsu no Yaiba available in both English and Japanese, the app (which surpassed 1 million cumulative downloads in May 2026) offers an autonomous and enjoyable reading experience. Students read not "to study," but "because they want to know what happens next," naturally achieving an overwhelming amount of English input.

In this collaboration with ELSA, this dense input from Langaku serves as the starting point. By combining it with ELSA's proprietary pronunciation correction AI and speaking coach, we build a self-driven learning environment where students naturally progress from input to output, thinking, "I want to enjoy my favorite series and express those lines in my own voice."

■ Program Learning Flow: "Read, Speak Aloud, and Act"

This program is intended for implementation as summer vacation assignments or summer intensive courses. It transforms traditional "workbook completion time" into "Playful English" time—a period of engaging with English joyfully—and expands English learning into "a time to express oneself in one's own voice" through the following three-step flow:

  1. Read (Overwhelming Input): First, students read their favorite manga on Langaku. Since illustrations, panel layouts, and the story aid comprehension, they are less likely to give up, allowing them to absorb a massive amount of authentic English expressions and contexts, such as characters' emotions and daily conversations.
  2. Speak Aloud (Safe Output): Students use ELSA to read aloud the lines whose context and meaning they already understand. The AI provides instant feedback on pronunciation, intonation, and fluency. Because they can practice alone as many times as they want, even students who feel anxious about speaking in front of others can participate with peace of mind.
  3. Act (Retention through Dramatization): Going beyond simple reading aloud, the program incorporates elements of "dramatization" (theatrical methods), where students immerse themselves in the characters and deliver lines with emotion. By speaking while linking emotion to the scene, retention in memory is enhanced from the perspective of Second Language Acquisition (SLA).

Research in SLA suggests that this type of learning—"voicing English with emotion after understanding it in context"—leads to higher memory retention compared to rote memorization of isolated vocabulary and grammar. Read. Understand the meaning in context. Speak aloud. Say it again with the character's feelings. Through this flow, English learning expands from "a time to choose the correct answer" to "a time to try expressing oneself in one's own voice."

■ Learning Effects of "Langaku" (Implementation Verification Data)

The educational effectiveness of "Langaku" has been confirmed through an implementation verification study conducted at a high school in Tokyo (announced in April 2026*). In this study, all second-year students utilized "Langaku" over a period of 150 days, achieving the following results:

  • Reading Volume: Achieved an average of 32,000 words (up to 332,000 words) of extensive English reading as self-study over 150 days. This volume is comparable to the total number of words covered in junior high and high school textbooks over six years (approx. 30,000 to 50,000 words).
  • English Exposure Time: 90.1% of students who used the app three or more times a week responded that their "time spent engaging with English increased."
  • Changes in Motivation: The percentage of students who responded "I want to study English more" increased from 48.1% to 75.7% (+27.6 pt). Furthermore, 54.5% of students who previously disliked English reported an improvement in their aversion to the language.
[Excerpts of Comments from Students]
  • "Because it's manga, it doesn't feel like studying, making it easier to engage with English."
  • "I want to know what happens next, so it's easy to keep up the habit."
  • "I can read my favorite manga, and it's educational to see how famous lines are said in English."

By combining this proven input experience with ELSA's speaking practice, this joint program connects the dots all the way to "expressing understood English in one's own voice" as a single learning journey, aiming to maximize educational efficacy.

*Announced on April 8, 2026: "Manga-based Extensive English Reading App 'Langaku' Officially Announces Launch for Educational Institutions" https://mantra.co.jp/ja/news/langaku-the-manga-based-extensive-reading-app-officially-announces-launch-for-educational

■ Program Overview

Starting in the summer of 2026, this program will be pilot-implemented at five selected schools as a summer intensive course to verify its effectiveness. Results will be announced based on measurement data collected before and after summer vacation.


Target Schools (In Japanese alphabetical order)

  • Azabu Junior and Senior High School
  • Seishokaichi Junior and Senior High School
  • Showa Yakka University Affiliated High School and Junior High School
  • Tokyo Seitoku University Junior and Senior High School
  • Rikkyo Niiza Junior and Senior High School

Schedule (Tentative):

  • Through July 2026: Conduct demo lessons; measure baseline reading comprehension, pronunciation scores, etc.
  • July–August 2026: Assign English manga reading and ELSA read-aloud practice as homework; run reading promotion campaigns.
  • September 2026 onward: Measure effectiveness; announce results at joint webinars and educational forums. (Depending on the scope of permission from publishers and copyright holders, expanding the program to a wider call for applicant schools will be considered in the future.)
■ Future Outlook: Continuous Sharing of Practical Knowledge with Schools

Through the verification of this program, both companies will meticulously analyze changes in students' English exposure time, reading volume, motivation toward pronunciation, and confidence in speaking English aloud.

The insights and practical knowledge gained from this pilot will be widely disseminated through joint webinars for educators and educational forums, continuously shared with partner schools, educators, publishers, and EdTech providers.

Langaku and ELSA will develop a new instructional model that empowers students to learn English according to their own interests and build confidence in speaking, thereby contributing to the advancement of English education in schools.

■ To Teachers Interested in the Program: Upcoming Updates Available

This program is an initiative that designs English learning from both sides—extensive reading (Langaku) and pronunciation/speech (ELSA)—driven by the students' own desire to "read and say it." The insights gained from this summer's verification will be introduced once the results are compiled.

For teachers thinking, "I would like to introduce this to our school next academic year or during the winter term," or "I would like to hear more details first," we will provide timely updates on verification results, seminar schedules, and future developments. If you are interested, please register via the form below.

▼ Click here to receive the latest information or make an inquiry: https://forms.gle/Bvxmr8XyfRhQCQ6Y7

■ Educational Expert Comment

Professor Hiroyuki Yagihashi, Department of English, Faculty of Letters, Seikei University

"When attempting to understand unfamiliar content in a language other than one's native tongue, learners face a heavy cognitive load because they must grapple with both the language and the storyline simultaneously. In this regard, reading manga in English—where the overall plot is already known in Japanese—offers the advantage of reducing the cognitive load of story comprehension, making it easier for learners to focus their attention on the English expressions themselves. By engaging with lines alongside illustrations, panel flows, scenes, and characters' emotions, learners can grasp 'in what situation, by whom, and with what intention an expression is used,' enabling them to link and learn linguistic <form>, <meaning>, and <use>.
Furthermore, the process of repeatedly voicing the understood lines to aim for more appropriate pronunciation, while adjusting based on instant AI feedback, strengthens the connection between letters, sounds, and meanings, and prompts awareness of pronunciation challenges. By adding activities where students roleplay as characters, it is believed that a richer linguistic experience—encompassing English-like intonation, rhythm, emotion, and communicative intent—will be accumulated.
Of course, simply reproducing lines from a manga will not instantly yield free conversation skills. However, using a familiar story as a stepping stone to shift English from an 'object of comprehension' to 'expressions used in one's own voice' can serve as a meaningful learning opportunity that bridges motivation, comprehension, memory, pronunciation, and speech, in light of findings from cognitive linguistics and second language acquisition research."
■ About "Langaku"

"Langaku" is an app that delivers a dense learning experience through extensive English reading using manga. While enjoying over 100 popular manga titles such as ONE PIECE and Demon Slayer: Kimetsu no Yaiba in English, users naturally acquire English proficiency.

[Proprietary Learning Support Features]
  • Switch between English and Japanese with a single tap on a panel.
  • Audio narration for all dialogue lines and words (equipped with an auto-play mode).
  • Dictionary and AI explanations for all lines and words to look up unfamiliar language on the spot.
  • AI explanations covering context-specific idioms and slang expressions unique to English.
  • Adjust the volume of reading in English to suit individual learning styles.
  • Save words and lines you want to memorize for later review.
  • Manage reading logs digitally to visualize the accumulation of learning.

Extensive reading is one of the most effective learning methods to accustom the brain to English. Enjoy reading your favorite manga and experience "English learning without studying," where your English skills improve before you know it.

[App Information]
■ About ELSA

ELSA (English Language Speech Assistant) is an AI-powered English speech support service designed to help users speak English more correctly and confidently. Founded in 2015 in San Francisco, USA, it is currently used by over 90 million users across more than 190 countries worldwide. In Japan, more than 200 educational institutions—including all prefectural high schools in Kyoto, all public junior high schools in Shibuya City, Toshimogaoka Joshigakuen, Mita International School, and Seiko Gakuin—have adopted ELSA as a tool to improve students' English proficiency.

ELSA excels in providing pronunciation feedback at the phoneme level, allowing learners to check their pronunciation, intonation, and fluency while practicing speaking English aloud as many times as they want. Its service for educational institutions supports speaking practice in school settings through features like assigning tasks to students, visualizing learning progress, and AI role-playing.

■ About Mantra Inc.

Mantra Inc. was established in 2020 under the slogan "Bring manga to the world in their own languages." The company engages in the research and development of AI technology specialized for manga, and provides tools such as "Mantra Engine," a translation tool that enables high-speed manga translation, and "Langaku," a manga-based extensive English reading app.

Mantra has received numerous accolades, including the HONGO AI Award (2019), Weekly Toyo Keizai's "Amazing Venture 100" (2020), the AAMT Nagao Award (2021), the JEITA Venture Award Early Edge Award (2022), the Electronic Publishing Award Challenge Mind Award (2024), the Google Play Best of 2025 (Self-Improvement Category) Grand Prize (2025), and the Appliv Best App Award (Learning App Category) Excellence Award (2025).

[Company Profile]
  • Company Name: Mantra Inc.
  • Representative: Shonosuke Ishiwatari, CEO
  • Address: 2F Sumitomo Fudosan Iidabashi Bldg., 2-3-21 Koraku, Bunkyo-ku, Tokyo 112-0004
  • Established: January 28, 2020
  • Capital: 1,000,000 JPY
  • Business Description: Research and development of machine translation technology specialized for manga, and provision of translation and English learning services.
  • URL: https://mantra.co.jp
■ About ELSA Japan LLC
[Company Profile]
  • Company Name: ELSA Japan LLC
  • Representative: Dai Imao
  • Address: Shibuya-ku, Tokyo
  • Business Description: Development and provision of the AI English conversation learning app and services supporting English proficiency improvement.
  • Official Website: https://jp.elsaspeak.com/
■ Inquiries
  • Mantra Inc. Public Relations: Norimine / Funakoshi
  • E-mail: info@mantra.co.jp
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