Takafumi Horie, former CEO of Livedoor, was born on October 29, 1972, in Fukuoka Prefecture. He is known by his nickname "Horiemon." He moved to Tokyo in 1991 after enrolling in the Department of Humanities, Division 3, College of Arts and Sciences, University of Tokyo. He founded On the Edge LLC in 1996 and dropped out. In 1997, he reorganized into a public company and attracted attention as a website production and management company during the early days of the Internet. In 2002, he acquired the business rights from the bankrupt Livedoor. In 2004, he proposed to acquire the Osaka Kintetsu Buffaloes and announced plans to establish a new baseball team in Tohoku, but neither plan came to fruition. However, "new entrant" ("new entrant") was selected as one of the buzzwords of the year, and he attended the award ceremony. The following year, he became the largest shareholder of Nippon Broadcasting System. His words, "within the realm of expectation," which he used to address the media during the takeover, also won the buzzword award.

In 2005, he ran for the House of Representatives general election in Hiroshima's 6th district, but was defeated. In 2006, he was arrested on suspicion of violating the Securities and Exchange Act and resigned from his position at Livedoor. Shortly after an article in the fashion magazine SENSE featuring an interview with CyberAgent CEO Fujita Susumu was published, his sentence of two years and six months in prison was finalized in April 2011. After serving his sentence in Nagano Prison, he was released on parole in March 2013 with approximately seven months of his sentence remaining. Before his incarceration, he was seen wearing his trademark Louis Vuitton T-shirt.