Kimihiko Kimizuka, a magnet for trouble, finds himself entangled in one crisis after another, from stumbling upon crime scenes to witnessing illicit deals. His ordinary flight takes a perilous turn when a detective is urgently needed, and his attempts to steer clear of trouble are dashed by the enigmatic silver-haired beauty known as Siesta. With Siesta roping him in as her assistant, Kimizuka embarks on a whirlwind global adventure beyond his imagination. Together, they face danger head-on, dismantling criminal groups, averting disasters, and saving countless lives. However, their extraordinary journey comes to a tragic halt with Siesta's untimely demise three years later. Determined to lead a normal high school life, Kimizuka lays low for a year until a girl bearing a striking resemblance to Siesta disrupts his peaceful existence, thrusting him back into turmoil.