Amari Seiji prepares to try the impossible: confessing to the most popular girl in school.
To raise his chances, he seeks out the school's rumored "love expert" - only to discover that she's actually a detective! Shiomi Yua rejects romance in favor of logic, but will still solve any mystery that comes her way. Stalkers, anonymous love letters or locked-room incidents, she'll do them all for a bag of snacks.
Smitten by her brilliance and quirky personality, Seiji forgets all about his original target and impulsively asks to become Yua's assistant.
This might be his greatest challenge yet, but can he solve his way to her heart?