The PlayStation Portable[a] (PSP) is a handheld game console developed and marketed by Sony Interactive Entertainment. It was first released in Japan on December 12, 2004, in North America on March 24, 2005, and in PAL regions on September 1, 2005, and is the first handheld installment in the PlayStation line of consoles. As a seventh generation console, the PSP competed with the Nintendo DS. Development of the PSP was announced during E3 2003, and the console was unveiled at a Sony press conference on May 11, 2004. The system was the most powerful portable console at the time of its introduction, and was the first viable competitor to Nintendo's handheld consoles after many challengers such as Nokia's N-Gage had failed. The PSP's advanced graphics capabilities made it a popular mobile entertainment device, which could connect to the PlayStation 2 and PlayStation 3, any computer with a USB interface, other PSP systems, and the Internet. The PSP also had a vast array of multimedia features such as video playback, audio playback, and has been considered a portable media player as well. The PSP is the only handheld console to use an optical disc format—in this case, Universal Media Disc (UMD)—as its primary storage medium; both games and movies have been released on the format. The PSP was received positively by critics, and sold over 80 million units during its ten-year lifetime. Several models of the console were released, before the PSP line was succeeded by the PlayStation Vita, released in Japan in 2011 and worldwide a year later. The Vita has backward compatibility with PSP games that were released on the PlayStation Network through the PlayStation Store, which became the main method of purchasing PSP games after Sony shut down access to the store from the PSP on March 31, 2016. Hardware shipments of the PSP ended worldwide in 2014; production of UMDs ended when the last Japanese factory producing them closed in late 2016.
Near the end of the second tournament, Kei Ikushima, after defeating Regulus in the finals, discovers that the underground laboratory's self-destruct mechanism has been activated. As she was about to make her escape, she would end up crossing paths with Eileen A. once again. Kei tried to escape the lab with Eileen, but she hesitated, instead telling Kei the answer she was looking: Kei was actually the daughter of none other than the CEO of Orion Corporation, Ranzou Kihara. She then gives Kei a letter before telling her to go on and leave the building without her. Kei hesitates at first but soon obliges as the lab eventually explodes, leaving Eileen behind, her fate unknown. Three years after the explosion at the Orion labs, Kei finds out more about her past from the letter Eileen gave her before the incident. She also found out that her DNA was taken for usage in Orion's Perfect Fighter Project, the very same set of experiments that orphaned her adoptive father Shin and ruined the lives of many others. Fast forward to several weeks before Kei’s 20th birthday, several attacks on various martial artists have been reported. All of them perpetrated by people who bore a striking semblance to Kei. As a result, Kei has been blamed for all the attacks, despite having no hand on them. Kei then began to suspect that it had something to do with the Perfect Fighter Project that Eileen had mentioned. Then, on the day of Kei’s 20th birthday, Orion announces the third Sentoki: Global Martial Arts tournament. Kei joins the tournament in order to cleanse her name and find out the truth of it all.
