Strength

Strength (ストレングス or STR) is part of the supporting cast in the OVA anime series Black★Rock Shooter. She is implied to be the "other self" of Yuu.

Appearance
Like Geshumaru, Strength uses mechanized weaponry. Her arms are made up of two huge mechanical arms called "Ogre Arm". She has a robotic tail with a vertebrae-like design that can move freely and her feet are metal stilts. She has a black hood with white flames on it and white ribbons at the base of her tail and knee highs. She has white eyes and short white hair as well.

Unlike in huke's artwork, however, in the OVA, Strength's eyes are hazel (with the circular pattern akin to all "other selves") instead of white. The reason for this change is unknown, but it is very likely done to give a connection point to Yuu, as she is the only other character with hazel eyes and eyes are used as a connection point for "other selves".

History
She is shown approaching Black★Rock Shooter and the Dead Master in their battles (but in a different part of the Otherworld), while at the same time Yuu's feelings at being "left out" grow darker.

Black★Rock Shooter (2012)
She is first introduced in Episode 4, in which she is seen dragging the beheaded Chariot behind her, and then throwing the body off of a cliff, after which the red eyes of Black★Gold Saw start appearing in the sky.

Later, while dreaming Mato briefly sees Strength standing in the same area where she was before, but does not take much notice because the scene quickly changes.