Yoko Wakana is a crazy cop in the Traffic division. She'll go to the extreme to bring suspects to justice. She first appears in A Fruitless Lunchtime of Full Metal Panic? Fumoffu as she chases after Kaname Chidori and Sousuke Sagara, but she ends up trashing her patrol car.
- The name Yoko means "light, sun, male" (陽) (you) and "child" (子) (ko).
- The name Yoko is alternate transcription name of Youko.
- Yoko's surname Wakana means "young" (若) (waka) and "vegetable" (菜) (na).