LEGAL
Terms and Conditions
Version 1.0 — Effective Date: 3 August 2026
Article 1 — Scope and Acceptance
These Terms and Conditions (“Terms”) govern the purchase and use of MugenSIM eSIM products
and related services (“Service”) offered by Mugen Links 合同会社 (Mugen Links G.K.) (“Mugen
Links,” “we,” “us,” or “our”) through the website mugensim.com (“Site”) and associated platforms
including Shopify. By completing a purchase on the Site, you confirm that you have read,
understood, and agree to be bound by these Terms. If you do not agree, you must not proceed with
any purchase. These Terms constitute a binding legal agreement between you (“Customer,” “you,”
or “your”) and Mugen Links under the laws of Japan.
Article 2 — Eligibility
The Service is available exclusively to persons who are non-residents of Japan at the time of
purchase. By placing an order, you represent and warrant that:
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You are not a resident of Japan;
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You are at least 18 years of age or have the legal capacity to enter into a binding contract under the laws of your country of residence;
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You are purchasing the Service for personal, non-commercial use unless otherwise agreed in writing with Mugen Links;
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All information you provide during the purchase process is accurate and complete.
Mugen Links reserves the right to refuse or cancel orders if it reasonably believes the eligibility
requirements have not been met.
Article 3 — Description of Service
MugenSIM provides prepaid eSIM profiles for use on compatible unlocked devices in Japan. The
Service enables data connectivity on the mobile network operated by our network partner
(“Operator”) in Japan. Key service characteristics:
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The eSIM profile is delivered via QR code to the email address provided at checkout.
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The Service is prepaid and non-renewable through the Site unless otherwise stated at the time of purchase.
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Service coverage, speed, and availability depend on the Operator’s network infrastructure and are subject to the Operator’s own terms and conditions.
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The Service does not include voice calls or SMS unless explicitly stated in the product description.
MugenSIM eSIMs are intended for use within Japan only. Use outside Japan is not
supported.
3.6 Network Operator Terms
The Service is provided over the mobile network of KDDI Corporation (“KDDI”), one of Japan’s
major telecommunications operators, acting as our affiliated network operator (“Operator”). The
provision of mobile network connectivity is subject to the Operator’s own service terms and
conditions (契約約款), which are incorporated into these Terms by reference to the extent they
apply to end users of the Service. By purchasing and using MugenSIM, you acknowledge and
agree to the following conditions arising from the Operator’s network terms:
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Single device use: The eSIM may only be active on one device at a time.
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Simultaneous use on multiple devices is not permitted under the Operator’s terms.
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Speed throttling: Where your data allowance is exhausted or where network congestion occurs, the Operator may reduce data transmission speeds to a maximum of 128 kbit/s or apply other speed restrictions in accordance with the Operator’s fair use policy.
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Network suspension: The Operator may suspend or restrict your network access in the event of network maintenance, emergency, or congestion, or where use of the Service is found to violate applicable terms or laws.
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No refund for unused data: Unused data at the expiry of the service validity period is forfeited. No refund is provided for unused data allowance.
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eSIM profile erasure: The Operator may erase the eSIM profile upon termination or expiry of the service, or where technically necessary. Mugen Links is not liable for any loss arising from such erasure.
Prohibited uses: In addition to the prohibited uses set out in Article 8 of these Terms, use of the Service is subject to the Operator’s prohibited use policy, which includes but is not
limited to: interference with network equipment; transmission of illegal, defamatory, or harmful
content; infringement of third-party intellectual property rights; impersonation; distribution of child
sexual abuse material; and any other act violating Japanese law or public order. The full terms and
conditions of the Operator are available at: https://sites.google.com/joy2call.com/sim/terms-and-conditions#h.qk4elwgsu5d. In the event of any conflict between these Terms and the Operator’s
terms regarding network use, the Operator’s terms shall prevail with respect to network-level
matters.
Article 4 — Device Compatibility and Roaming
It is your responsibility to ensure that your device is compatible with eSIM technology before
purchase. Compatible devices must:
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Support eSIM functionality;
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Be unlocked from any carrier restrictions;
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Be compatible with the frequency bands used by the Operator in Japan.
Mugen Links does not guarantee that any specific device model will be compatible with the
Service. Incompatibility of your device does not entitle you to a refund unless otherwise provided
under Article 9 of these Terms. It is your sole responsibility to disable data roaming on your home
carrier's SIM or plan before travelling to Japan. Failure to do so may result in unintended roaming
charges being applied by your home network operator upon arrival, regardless of whether the
MugenSIM eSIM is active. Mugen Links accepts no liability for any charges, costs, or damages
arising from the Customer's failure to manage their home carrier settings prior to travel.
Article 5 — Ordering and Payment
5.1 Order Process
Orders are placed through the Site. Upon completing your order, you will receive an order
confirmation by email. This confirmation does not constitute acceptance of your order; acceptance
occurs when the QR code is delivered to your email address.
5.2 Prices and Taxes
All prices displayed on the Site are inclusive of Japanese Consumption Tax (“JCT”) at the
applicable rate. JCT applies to all sales regardless of the Customer’s country of residence, in
accordance with Japanese tax law. Prices are displayed in Japanese Yen (JPY) unless otherwise
stated. Currency conversion, if any, is handled by your payment provider and Mugen Links bears no responsibility for exchange rate fluctuations or foreign transaction fees.
5.3 Payment Processing
Payments are processed through Shopify Payments. By providing your payment information, you
authorize Mugen Links to charge the total amount due for your order. Mugen Links does not store
your credit card or payment details; these are handled directly by Shopify’s secure payment
infrastructure. Mugen Links reserves the right to refuse or cancel any order in the event of
suspected fraud, unauthorized use of payment methods, or technical errors in pricing.
Article 6 — eSIM Delivery and Activation
Following successful payment, the eSIM QR code will be delivered to the email address provided at checkout, typically within a short processing time. Mugen Links does not guarantee delivery within any specific timeframe. You are solely responsible for:
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Ensuring the email address provided at checkout is correct and accessible;
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Safeguarding the QR code once received;
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Following the activation instructions provided with the QR code.
Each QR code is for single use only. Once the eSIM profile has been downloaded to a device, the
QR code cannot be reused. The eSIM profile becomes active upon download to your device. The
validity period of the service plan begins from the date of activation or the date of first use, as
specified in the product description at the time of purchase.
Article 7 — Service Validity and Expiry
Each MugenSIM plan has a defined validity period as stated in the product description at the time
of purchase. Upon expiry of the validity period or exhaustion of the included data allowance
(whichever occurs first), the Service will be suspended automatically. Unused data or remaining
validity cannot be carried over, refunded, or transferred to another plan or account unless
expressly stated otherwise. The maximum usability period for any MugenSIM plan is 180 days from activation. After this period, the line will be terminated regardless of remaining data balance. The validity period of each plan is calculated in calendar days under Japan Standard Time (JST,
UTC+9). A calendar day runs from 00:00 to 23:59 JST. The first day of validity commences upon
connection of the eSIM to the Operator’s network, and expires at 23:59 JST on the same calendar
day, regardless of the time of activation. Customers who activate their eSIM late in the day should
be aware that the first calendar day may provide less than 24 hours of service.
Article 8 — Acceptable Use
You agree to use the Service solely for lawful purposes and in accordance with these Terms.
You must not use the Service:
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In violation of any applicable Japanese law or regulation, or the laws of your country of residence;
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To transmit, distribute, or store any content that is unlawful, harmful, defamatory, obscene, or otherwise objectionable;
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To engage in any activity that interferes with or disrupts the Operator’s network or infrastructure;
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To generate excessive or abnormal traffic that places unreasonable demands on network resources;
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For commercial resale, sub-licensing, or redistribution of the Service without prior written consent from Mugen Links;
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For any fraudulent, deceptive, or unauthorized purpose.
Mugen Links and the Operator reserve the right to suspend or terminate the Service immediately
and without prior notice in the event of a breach of this Article.
Article 9 — Refunds
Due to the digital nature of the Service, all sales are final once the QR code has been delivered to
your email address. Mugen Links does not offer refunds after delivery of the QR code.
Article 10 — Service Interruptions and Limitations
The Service depends on the Operator’s mobile network infrastructure. Mugen Links does not own
or operate the network and cannot guarantee uninterrupted, error-free, or continuous service
availability. Mugen Links shall not be liable for service interruptions, degradation, or unavailability
caused by:
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Network maintenance, upgrades, or outages by the Operator;
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Natural disasters, extreme weather conditions, or force majeure events;
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Radio propagation conditions, geographic limitations, or physical obstructions;
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Actions or omissions of third parties, including but not limited to infrastructure providers;
Government orders, regulatory actions, or legal requirements;
Your device’s hardware, software, or configuration.
Article 11 — Limitation of Liability
To the fullest extent permitted by applicable law, Mugen Links’ total liability to you for any claim
arising out of or in connection with these Terms or the Service shall not exceed the amount paid by you for the specific order giving rise to the claim. Mugen Links shall not be liable for any indirect, incidental, special, consequential, or punitive damages, including but not limited to loss of data, loss of profits, loss of business, or reputational damage, whether arising in contract, tort, or
otherwise, even if Mugen Links has been advised of the possibility of such damages. Nothing in
these Terms excludes or limits any other liability that cannot be excluded or limited under
applicable Japanese law.
Article 12 — Intellectual Property
All content on the Site, including but not limited to the MugenSIM brand, logo, trademarks, product
names, text, graphics, and software, is the property of Mugen Links or its licensors, partners, etc.,
and is protected by applicable intellectual property laws. You are granted a limited, non-exclusive,
non-transferable, and revocable license to access and use the Site and Service for personal, non-
commercial purposes. You may not reproduce, distribute, modify, or create derivative works from
any content on the Site without prior written permission from Mugen Links.
Article 13 — Modifications to Terms and Service
Mugen Links reserves the right to modify these Terms at any time. Changes will be published on
the Site with an updated effective date. Your continued use of the Service after the effective date of any changes constitutes acceptance of the revised Terms. Mugen Links also reserves the right to modify, suspend, or discontinue the Service or any part thereof at any time without prior notice.
Mugen Links shall not be liable to you or any third party for any such modification, suspension, or
discontinuation.
Article 14 — Privacy
The collection and processing of your personal data in connection with the Service is governed by
our Privacy Policy, available at mugensim.com/privacy. By using the Service, you acknowledge and agree to the terms of our Privacy Policy.
Article 15 — Governing Law and Dispute Resolution
Article 15 — Governing Law and Dispute Resolution
These Terms shall be governed by and construed in accordance with the laws of Japan, without regard to its conflict of law principles. Any dispute arising out of or in connection with these Terms or the Service shall be submitted to the exclusive jurisdiction of the Tokyo District Court as the court of first instance. You irrevocably waive any objection to the laying of venue in Tokyo, Japan. Before initiating formal legal proceedings, you agree to contact Mugen Links (www.mugenlinks.com) to attempt to resolve any dispute amicably within 30 days.
Article 16 — Severability
If any provision of these Terms is found to be invalid, unlawful, or unenforceable by a court of
competent jurisdiction, such provision shall be modified to the minimum extent necessary to make
it enforceable, or severed if modification is not possible. The remaining provisions of these Terms
shall continue in full force and effect.
Article 17 — Entire Agreement
These Terms, together with the Privacy Policy and any product-specific terms communicated at the time of purchase, constitute the entire agreement between you and Mugen Links with respect to the Service and supersede all prior agreements, representations, and understandings.
Article 18 — Contact
For any questions, complaints, or requests related to these Terms or the Service, please contact:
Mugen Links LLC.