Koutarou Yui

Koutarou Yui stands out within Matori as a pharmacological virtuoso whose mastery of drug compounds borders on the extraordinary. He harbors an almost obsessive fascination with the heroine's rare drug-resistant constitution, occasionally shocking his colleagues with bold requests for her DNA samples. His perpetually chaotic desk and eccentric behavioral patterns have firmly cemented his reputation as the team's resident oddball. Yet when the stakes are highest, Yui's razor-sharp composure and commanding presence emerge without warning—revealing a dependable elite operative who proves absolutely indispensable when it matters most.