|Voice Actor||Yoshino Nanjō|
Kokoro Akechi (明智 小衣 Akechi Kokoro) is the leader of Genius Four, a police investigation unit responsible for the Gentlemen Thieves incidents. She is a bossy girl who looks down on Milky Holmes since they lost their Toys and always claims to boast a massive IQ. She smacks Sherlock with a golden mask whenever she calls her "Kokoro-chan".
- The name Kokoro means "small" (小) (ko) and "clothing, garment" (衣) (koro).
- Kokoro's surname Akechi means "bright" (明) (ake) and "wisdom, intellect" (智) (chi).