Itsuki Koizumi 古泉一樹

Height: 178 cm (5'10")

Occupation: Student (grade 11), Vice Commander,

Itsuki is the last member to have joined the SOS Brigade, having been recruited by Haruhi Suzumiya as a "mysterious transfer student". Itsuki is constantly smiling and always speaks in a formal and polite manner. He is also prone to giving long and detailed explanations, usually illustrated by exaggerated hand gestures. Itsuki's fondness for speculation often causes him to produce explanations for situations involving the SOS Brigade, its members and related events. Itsuki only tends to share these explanations and theories with Kyon, and also enthusiastically plays different kinds of board games with him to pass the time, despite losing all the time, although Kyon suspects that he may be doing so on purpose.

Out of the three Brigade members, Kyon is the least fond of Itsuki. He often finds himself annoyed with Itsuki's plastic smile, his willingness to acquiesce to Haruhi's outrageous schemes, playful teasing and his various forays into his psychological and philosophical theories. He is also distrustful of Itsuki's intentions, comparing him to Yuki Nagato when it comes to deciphering his expressions.!~