It has been confirmed that the Shibuya which Sora will be in Kingdom Hearts 4 is not related to the Shibuya in The World Ends With You. This would have been an easy things for fans to expect, but more information about the somewhat complicated issue of just what Quadratum is in Kingdom Hearts has come to light from series director Tetsuya Nomura.
This differing identity of Shibuya and Quadratum may come as a surprise to Kingdom Hearts 4 fans, as two previous installments of the game, Kingdom Hearts: Dream Drop Distance and Kingdom Hearts 3, both had references to (as well as characters from) the series guest star in the main story. Speculation had risen on whether the sequel would be taking place in the world of The World Ends With You due to characters Neku, Shiki, Joshua, Beat and Rhyme appearing during the events of Dream Drop Distance.
Related: Everything Kingdom Hearts 4's New Trailer Reveals About Its Story
But Nomura confirmed in an interview with Famitsu (as reported by Polygon) that these locations are two separate entities, so it seems that a crossover with The World Ends With You isn't in the cards for Kingdom Hearts 4. Nomura reported during the interview that main character Sora is located in what seems to be an alternate reality of Shibuya called Quadratum in the trailer for Kingdom Hearts 4, and this will be a subject of narrative contrast in the game itself.
While stating this, Normua specifically confirmed that this Shibuya is not the same location where the Reaper's Game takes place. This would make the location in question unique in that it is not only unrelated to the game franchise that was expected, but that it also is considered its own universe and may not even be related to any franchises owned
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