The Secret of Girls (originally named なぃしょのつぼみ in Japanese) is a cartoon with the theme of sex education created by Japanese girl cartoonist Yuuchi You, and an OVA adapted from this cartoon. Since 2004, The Girl's Secret Mind has been serialized in magazines of four-year-old primary schools and five-year-old primary schools. Describe the "somewhat incredible" combination of elements in daily life and love, and the physical and mental growth of the protagonists.