The Calling

Kira (on left) and Lina (on right) Shapards. When Kira was a kid back on Earth, in New York's darktowns, among gangs and bandits, she had a twin-sister, Lina. But by dealing with criminals, Kira was always putting her sister's life in danger. One day some criminal bastards killed her. Since then Kira can't forgive herself for failing to protect her only family and closest friend - her twin, Lina.

So, this pic is some kind of illusion or dream Shep's having about her sister. Cause she misses her so much, since the day she's gone.

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Mass Effect series, Shepard, earthborn origin (c) Bioware
Kira and Lina Shepards (c) me