In the first episode it is revealed that M9's full name is M-IYU9. This and the fact that she bears a crude sword arm herself seems to indicate that she was based on Miyu's design, although how Schwartz would have obtained that information is unclear.
MIYU appears in the second episode of the OVA. She refers to M9 as her sister, and states that she must put M9 back to sleep before her ability to copy the powers of her opponents makes her too powerful. She already knows Rena before the events of the OVA.
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