1. Scope and Acceptance

These Terms apply to all users of the Service and form a binding agreement between you and the operator (“we,” “us,” or “our”). Any guidelines, policies, notices, and additional terms we post or provide in connection with the Service (“Supplemental Terms”) are incorporated by reference. If there is a conflict, the Supplemental Terms will control for the relevant subject matter.

2. Definitions

3. Accounts and Eligibility

1. The Service is account-based. As a general rule, guest use (without login) is not supported, and core learning features may require you to sign in.
2. You must provide accurate registration information and keep it up to date. You are responsible for maintaining the confidentiality of your credentials and for all activities under your account.
3. We may refuse registration, suspend, or terminate accounts where we reasonably believe there is fraud, abuse, policy violations, or legal risk.

4. Paid Membership, Billing, and Stripe

The Service operates on a paid membership model. Creating an account and signing in may be treated as your start of service usage as a paid member, and you may be subject to subscription billing through Stripe.

If your subscription is not active, you cannot use core learning features such as registering materials, generating quizzes, and taking quizzes.

We do not store your full payment card details. Payment processing is handled by Stripe according to Stripe’s terms.

5. Cancellation, Changes, and Refunds

You may view billing history, update payment methods, change plans, or cancel your subscription via the Stripe Customer Portal (or another method we designate).

Refunds or prorations are provided only where required by applicable law or where we explicitly state otherwise at purchase. If payment fails or a chargeback occurs, we may restrict access or suspend the account.

6. Multi-Device Access

When you sign in with the same account, you may access shared materials, quiz sets, and learning history from different devices (e.g., web browsers and macOS app). Availability depends on the Service’s supported platforms and may change over time.

7. User Content and Intellectual Property

1. Your ownership. You retain ownership of your User Content. As a basic policy, we treat the contents of your study materials as your intellectual property and do not share or secondarily use them externally.
2. License to operate the Service. You grant us a non-exclusive, worldwide license to host, store, process, transform, and display your User Content solely to provide and improve the Service (e.g., generating quizzes and showing your learning history).
3. No sale or public distribution. We do not sell your User Content or publicly distribute it without your consent. However, we may use service providers (e.g., hosting, AI processing) to process your User Content as needed to provide the Service, as described in Section 11.
4. Your responsibility. You represent that you have all rights necessary to upload and use your User Content and that it does not violate any law or third-party rights.

8. AI-Generated Output and Quality Notice

The Service may use AI to generate quizzes or related outputs from your materials. AI outputs may be inaccurate, incomplete, or contain unintended content.

As a service quality standard, we aim to avoid presenting as factual any content that is not present in your study materials, even when using AI. However, we do not guarantee correctness or completeness, and you remain responsible for reviewing outputs before relying on them.

9. Prohibited Conduct

You agree not to:

• Use the Service in violation of any law or regulation.
• Attempt unauthorized access, probe vulnerabilities, or disrupt the Service.
• Upload content that infringes third-party rights or contains unlawful material.
• Abuse billing systems (fraud, repeated chargebacks, circumvention of access control).
• Reverse engineer the Service except to the extent permitted by law.
• Use the Service to leak personal data or confidential information of others.

10. Security, Anti-Abuse, and reCAPTCHA

We employ reasonable security measures to protect the Service. To prevent bot registrations and abuse, we may require human verification during sign-up (e.g., Google reCAPTCHA).

11. Privacy and Third-Party Services

We handle personal information in accordance with applicable laws (including Japan’s Act on the Protection of Personal Information). We do not use personal information (e.g., email address) outside its intended purposes, and any third-party provision is limited to the scope defined by these Terms and our Privacy Policy.

The Service relies on third-party providers for essential functions:

• Payments: Stripe (Checkout, Customer Portal)
• Anti-bot / security: reCAPTCHA
• Hosting / storage: cloud infrastructure and storage systems
• AI processing: AI service providers (if enabled)

Details about what we collect and how we process data are described in our Privacy Policy.

12. Data Retention, Backups, and Deletion (Hard Delete)

We may perform automated backups of certain databases at least once per day and maintain documented recovery procedures for important user data (materials, quiz sets, learning history).

We may support irreversible deletion (“Hard Delete”) to meet GDPR-aligned compliance requirements, including deletion of user-related datasets such as materials, quiz sets, sessions, and user records, subject to legal obligations (e.g., fraud prevention, dispute resolution).

13. Service Changes, Suspension, and Termination

We may modify, suspend, or discontinue the Service (in whole or in part) at any time. We will try to provide advance notice for material changes where reasonable, but this is not always possible (e.g., security incidents).

We may suspend or terminate your access if we reasonably believe you violated these Terms, engaged in abuse or fraud, or created legal or security risk. Where feasible, we may provide notice.

14. Disclaimers

THE SERVICE IS PROVIDED “AS IS” AND “AS AVAILABLE.” TO THE MAXIMUM EXTENT PERMITTED BY LAW, WE DISCLAIM ALL WARRANTIES, INCLUDING IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT.

We do not guarantee that the Service will be uninterrupted, error-free, or that AI-generated outputs will be accurate or suitable for your specific learning or testing needs.

15. Limitation of Liability

TO THE MAXIMUM EXTENT PERMITTED BY LAW, WE WILL NOT BE LIABLE FOR INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR FOR LOSS OF PROFITS, DATA, OR GOODWILL, ARISING FROM OR RELATED TO YOUR USE OF THE SERVICE.

EXCEPT FOR OUR WILLFUL MISCONDUCT OR GROSS NEGLIGENCE, OUR TOTAL LIABILITY ARISING OUT OF OR RELATING TO THE SERVICE WILL NOT EXCEED THE AMOUNT YOU PAID TO US FOR THE SERVICE DURING THE TWELVE (12) MONTHS PRIOR TO THE EVENT GIVING RISE TO THE CLAIM.

16. Indemnification

You agree to indemnify and hold us harmless from any claims, liabilities, damages, losses, and expenses (including reasonable legal fees) arising from or related to your use of the Service, your User Content, or your violation of these Terms.

17. Changes to These Terms

We may update these Terms from time to time. If we make material changes, we will provide notice by reasonable means (e.g., posting within the Service). Your continued use of the Service after the effective date means you accept the updated Terms.

18. Governing Law and Jurisdiction

These Terms are governed by the laws of Japan. Any dispute arising out of or relating to these Terms or the Service will be subject to the exclusive jurisdiction of the court having jurisdiction over our principal place of business in Japan, unless otherwise required by law.

19. Specified Commercial Transactions Act (Japan) Notice

As a subscription service, we will display required information on our website, including merchant name, address, contact details, payment methods, and cancellation policy, in compliance with the Specified Commercial Transactions Act.

For detailed information, please refer to our Specified Commercial Transactions Act page.

We also comply with Stripe's terms and brand guidelines and use Stripe Checkout / Customer Portal without handling prohibited card data.

20. Contact

If you have questions about these Terms, please contact us through our contact form.