MANAGEMENT

Koki Kimura previously worked for a variety of companies, including those in the electrical equipment and mobile content industries. He joined mixi, Inc. (now MIXI, Inc.) in 2008. He oversaw operations consulting for the Games Department and worked on several communications-based games, including “Sunshine Ranch.” Afterward, he helped launch the MONSTER STRIKE Project. He was made a corporate officer in November 2014, appointed to the board of directors in June 2015, then became a director and corporate officer in April 2018. In June 2018, he became the president and representative director of MIXI and remained a corporate officer. In April 2020, he remained the president and representative director. In March 2021, he received a master’s degree from the Graduate School of Sport Sciences at Waseda University. In April 2022, he was made a senior corporate officer of MIXI and remained the president and representative director. In April 2023, he was made the CEO of MIXI and remained the president and representative director. He is currently the president, representative director, CEO, and a senior corporate officer of MIXI as of December 2023.

After working at a music distribution company and a consulting firm, Kohei Shimamura joined mixi, Inc. (now MIXI, Inc.) in April 2016. Working in the Corporate Planning Division of the Corporate Promotion Department, his duties included business support, corporate management, and M&A promotion. In October 2017, he was made general manager of the Corporate Planning Division, and in April 2019, he was put in charge of corporate management sections as the chief general manager of corporate planning. In April 2020, he was appointed corporate officer and chief general manager of corporate promotion. In April 2023, he was appointed senior corporate officer and CFO. He is currently a director, senior corporate officer, and CFO of MIXI as of June 2025.

Tatsuma Murase joined E-Mercury (now MIXI, Inc.) in 2005. He helped develop the social network “mixi”. After leaving the company in 2009, he worked for a variety of companies in the game industry before returning to MIXI in 2013. He mainly oversaw the development of MONSTER STRIKE. In July 2016, he was placed in charge of all XFLAG engineers as executive director of XFLAG Studio’s Game Development Division. In April 2018, he was made a corporate officer and CTO. In June 2019, he was appointed to the board of directors and remained as CTO and a corporate officer. In April 2020, he remained CTO and a director. In April 2022, he was made a senior corporate officer and remained CTO and a director. He is currently a director and a senior corporate officer of MIXI as of April 2023.

As a university student in 1997, Kenji Kasahara was inspired by the IT business case studies he covered in seminars, along with the rise of online businesses in Silicon Valley. He sensed an opportunity and started a recruitment website in November 1997. In June 1999, he incorporated the company and became its representative director. His next step was to launch the social networking service “mixi” in February 2004. The company’s name was changed to “mixi, Inc.” (now MIXI, Inc.) in February 2006 and it was listed on the Tokyo Stock Exchange’s Mothers market in September of the same year. Kenji was made chairperson of the board of directors in June 2013. In April 2018, he remained as chairperson and was made a corporate officer. In June 2021, he remained a director. He is the founder of MIXI and as of April 2022, he is currently a director and senior corporate officer.

After gaining experience in venture capital firms and startups, Sho Okuyama joined mixi, Inc. (now MIXI, Inc.) in April 2016. He has worked in the Corporate Planning Division and Investment Division, where he oversaw subsidiary support, business development, M&A, PMI, and startup investment, and led the investment sections. He was appointed a corporate officer in April 2022 and has served as a senior corporate officer since April 2023. As of October 2025, He was appointed and has served as director in Pointsbet since October 2025.

Kanji Kobayashi joined mixi, Inc. (now MIXI, Inc.) in 2007 after receiving his graduate degree. As a legal professional, he engaged in general legal work related to the company’s services. In April 2017, he became general manager of the Legal Affairs Division, with primary responsibilities being general corporate legal affairs, intellectual property, M&A, and crisis management response. He was appointed corporate officer in April 2019, and he is a senior corporate officer as of April 2022.

Sadaaki Kaneyoshi started his career as a developer on the Metal Gear series at Konami Digital Entertainment Co., Ltd. He served as the producer, director, and level designer for Dragon Collection, leading the title to great success. He was then responsible for console and mobile games, being involved in the releases of numerous titles. In 2021, he retired from his position as senior managing corporate officer and continued production activities at Konami on an independent basis, contracted as a creative advisor. He joined the MIXI in April 2025 and was appointed as a corporate officer and general manager of the Entertainment Creation Division of MIXI. He is currently a senior corporate officer of MIXI as of April 2026.

After graduating, Naoki Kameyama joined an information and telecommunication systems company, where he was involved in vulnerability assessment services. He joined mixi, Inc. (now MIXI, Inc.) in June 2015. He has mainly been engaged in information security related activities such as vulnerability assessment, Iaas monitoring, CSIRT, education/training, zero trust, and various awareness-raising activities at MIXI. In January 2021, he became the general manager of the Security Division of MIXI’s Development Department. He is currently a corporate officer, the general manager of the Security Division, and the CISO of MIXI as of April 2023.

After joining a design firm, Yoshiyuki Yokoyama worked as a freelancer before starting his own design company, which he later sold. He then worked as head of design at 4travel, Inc. (now Kakaku,com, Inc.) and corporate officer (in the areas of design / content creation) at Rich Media Co., Ltd. (now Sharing Beauty Co., Ltd.) before joining MIXI in January 2019. As of October 2021, he is the chief general manager of MIXI’s Design Department. He is also currently a corporate officer and the CDO of MIXI as of April 2023.

After finishing a postgraduate degree, Junpei Yoshino joined mixi, Inc. (now MIXI, Inc.) in 2008 as an engineer. After working on the infrastructure of the social networking service “mixi”, he was involved in application operations. He has since been involved in various developments related to IP-based communication, from physical infrastructure, server operation, and networking to video processing and filming. In May 2019, he was appointed general manager of the Infrastructure Division. As of April 2022, he is the chief general manager of MIXI’s Development Department. He is currently a corporate officer and the CTO of MIXI as of April 2023.

After working for two IT venture companies, Keisuke Mishima joined mixi, Inc. (now MIXI, Inc.) in October 2012. He was in charge of platform planning for “mixi Games” and released two mobile games as new ventures. He then worked as a planner on MONSTER STRIKE shortly after its release, and was involved in management operations. After working as a director on a new game title, he has been involved in planning and management for MONSTER STRIKE again since 2016. In 2019, he was appointed general manager of game operations in the MONSTER STRIKE Business Department. He is currently chief general manager of the Digital Entertainment Operations Department as of February 2024, as well as a corporate officer of MIXI as of April 2025.

Masaya Tamura joined mixi, Inc. (now MIXI, Inc.) in 2009, assuming a business position. After working in ad sales for the social networking service “mixi”, he became engaged in platform alliances such as content development for “mixi Apps and Games”. In 2013, he was in charge of marketing for MONSTER STRIKE upon its release, and from August 2015, oversaw the marketing of MONSTER STRIKE both in Japan and abroad as the general manager of the Marketing Division. He then became involved in business development with a focus on merchandising and events, and in April 2018, he was appointed as a corporate officer and the chief general manager of the Live Experience Department of MIXI. In 2019, he was appointed to the Board of Directors of Chiba Jets Funabashi Co., Ltd. and as of July 2020, he is currently the president and representative director of that company. He is currently a director of Tokyo Football Club as of June 2025. He is currently a corporate officer of MIXI as of April 2026.

Hidetaka Kojo joined MIXI in 2006 as an engineer. After working in the Systems Development Division at MONSTER STRIKE Studio within the XFLAG Business Department, he joined the Development Department in September 2018. He has been engaged in the design and operation of infrastructure and databases for many years, contributing to the establishment of stable systems for operating large-scale services. He also led the development of a voice chat system and AI middleware, furthering the sophistication of MIXI’s technological infrastructure. For mixi2, he solved technical issues related to its infrastructure and databases, contributing to the launch of the service. He is currently a MIXI fellow as of April 2026.

As executive director at The Walt Disney Company (Japan) Ltd., Taichi Takeno was responsible for game business in Japan and played a key role in the launch of Disney Tsum Tsum and Disney Twisted-Wonderland. He was also involved in building partnerships with domestic and international companies and creators. He became an independent IP content consultant in 2025 and then joined MIXI in April 2026. He is currently a MIXI fellow as of April 2026.

Takehito Masui joined Warner Music Japan Inc. in 2010. As a director, he was involved with the creation of hits for artists such as Tomohisa Yamashita. He then launched the Atarashiichizu project as a producer and was involved in the “BAD HOP THE FINAL at TOKYO DOME” concert: the first solo performance by a Japanese hip-hop artist at Tokyo Dome. In 2021, he became an executive producer at Warner Music Entertainment, and in 2023, he became a corporate officer and manager of the strategic planning section of Warner Music Entertainment. He joined MIXI in April 2025 and was appointed executive producer and special delegate of the President’s Office. He is currently a MIXI fellow as of April 2026.