I don't even know what this game or franchise is but figured someone may like this news so:
From Kotaku:
A movie based on video game Oneechanbara was today announced in Japan. TV star Eri Otoguro will play Aya, bikini model Chise Nakamura will play little sister Saki and idol Manami Hashimoto will play Reiko. The characters and some stills can be seen below.
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It's was the first time I've ever worked in a bathing suit, so I was a little worried at first. Though, the costume was really cool, and I was able to play the part. We filmed during the winter, so it was a little chilly. I don't think you'd see a person dressed like this in winter.