D5

Base: Mermaid Island
Type: Unkown
Height: 165 cm
Eye Color: Brown
Hair Color: White/Blonde
Hairstyle: Long
Breast Weight: 8.8 kg
Cup: L
BWH: 105-60-88

D5 is mysterious girl who was transferred to the Mermaid Island later in the series. She is working with Momoka Sagara and E9.

(Source: Valkyrie Drive Wiki)