The Melancholy of Haruhi Suzumiya Season 1 episode 13 (2006)

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Kyon is dragged into helping Haruhi attempting to investigate what happened to Ryoko's strange disappearance without notice. After a fruitless search, Haruhi tells Kyon about her earlier years, and how she changed from an ordinary girl into her present state. Later that day, Itsuki tells Kyon about the theory of the anthropic principle correlating with Haruhi, and he believes that Kyon is the reason why Haruhi was able to wish of such extraterrestrial beings to exist. Itsuki brings Kyon into a sealed reality, where the latter watches the espers destroy a blue giant entity subconsciously created by Haruhi. When returning to his house, Kyon is told by Itsuki to look after Haruhi.