Itsuki Koizumi

Itsuki Koizumi is a character from the anime and light novel series Suzumiya Haruhi no Yūutsu. He is known for his mysterious and calculated demeanor, often involving himself in activities of the SOS Brigade, where he showcases his keen observational skills and logical mind. An avid fan of board games and a member of the Mystery Science Club, Itsuki is both athletic and sharp-witted. He maintains a friendly but somewhat distant relationship with the protagonist Kyon, engaging in philosophical discussions while subtly observing Haruhi and other club members. Itsuki is often seen as a counterpoint to Kyon's more grounded perspective, and he harbors an interest in Haruhi's unusual behaviors as part of the natural phenomena he studies.