Tsuruya is the hyperactive friend of Mikuru, notable for her loud voice, ankle-length hair, and prominent tooth. She possesses a cheerful and friendly disposition. She is also prone to long fits of unrestrained and intense laughter at things she considers even the slightest bit humorous. Her fang-like tooth gives her an idiosyncratic speech pattern, causing her to misspeak words by leaving out syllables. Her speech pattern is often accompanied with a lisp and her catch phrases "megas" and "nyoro". Her knowledge of the SOS Brigade comes almost exclusively from Mikuru. She is also the heir of the Tsuruya family, which purportedly collaborates with Itsuki's Agency. It is also unknown if Tsuruya has a secret identity or agenda. Though she is not a brigade member, Tsuruya is still often used as an extra body for some of the Brigade's activities.