Natsumi Mizushima (水嶋 なつみ, Mizushima Natsumi, born May 7, 1984) is a Japanese retired professional wrestler, better known by the ring name Natsuki☆Taiyo (夏樹☆たいよう, Natsuki☆Taiyō). Making her debut for All Japan Women's Pro-Wrestling (AJW) in January 2004, Mizushima quickly affiliated herself with Nanae Takahashi, following her out of AJW in 2006 and to Pro Wrestling Sun and NEO Japan Ladies Pro Wrestling, with the two forming the Passion Red stable with Kana in the process.