Musubi would drive me crazy. I get she's super innocent and full of love but I can't imagine being with someone that dim witted.
Ku is cool and all but that's creepy. Having her around is like taking care of the little kid. She's got a cool power I'll give her that. But even if you're goal is just to win The Sekirei Game I don't even think she's that good of a pick. Okay I'll say she's a great them player but she's not the one I'd pick if I just had to pick one.
Matsu's really interesting but she never displayed any kind of fighting ability or any special type of power at all. Maybe she could do more if motivated but who knows?
I think Tsukiumi would have to be the choice for me out of the four. I'll admit her personality probably will keep her from winning the game. I think she's powerful enough when winged but I think even then there's Sekirei who'd beat her.
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