Sinmore (シンモラ, Shinmora) is the younger sister of Eikþyrnir Surt.
When Surt and his closest friend Aquarius Camus were children, Camus was training near the snowy hills that their village lived next. However, he accidently triggered an avalanche, causing the avalanche to bury Sinmore alive and killing her. Her older brother Surt managed to dig out her body. After she was buried, her death was what forced her brother to become vain and cruel, which made him promise to never have a family, never find friends, or never know love.
Sinmore's death also still caused Aquarius Camus to become strickened with grief for years that after he was revived from the dead, he was forced to join forces with Surt and The God Warriors of Asgard. When Camus turns against his old friend, she was still mentioned several times. Seeing Surt in the flashback crying is revealed that he loved Sinmore like any brother would love his own sister.