[RapidPotential]

Originally Posted by XFire

Which side is the sisters real personality? And is she really his sister in the first place, or did they fake that to have someone close to him?

Spoiler for Sister:

From what I can understand of the information I got about the sister, she's actually his sister-in-law, apparently, so they have no blood-relation to each other.

With regards to her personality, she appears to have an "Imouto Mode" and a "Commander Mode", which she kinda switches in between different situations.

Correct me if I'm wrong though (information taken from the Japanese Wikipedia).