AC9171

 is a red blood cell in the Cells at Work! series that works inside the host's body.

Appearance
AC9171 has dark brown hair and eyes. As a red blood cell, he wears the standard red blood cell uniform.

Personality
Not much is known about AC9171, but he acted cordial toward a female red blood cell.

History
He is a target of Pneumonia Coccus after U-1146 gives chase to him in the alveolus. He is seen transporting some nutrients to be delivered while being targeted.