Detective Conan: Shrunk at the Start, Haibara's One and Only

When an undercover cop transmigrates into the Black Organization as a codename agent, his mission is clear: expose their crimes and save the Miyano sisters. But saving Akemi and Shiho comes at a devastating cost—forced to take the experimental drug APTX4869, he shrinks into a child. During their desperate escape, an accident steals his memories and speech, leaving him able only to murmur broken sounds. Now Haibara must protect the boy who once protected her, vowing to care for him no matter how long it takes. In a world of deadly secrets and shrinking bodies, can lost memories ever be recovere…