Bareteru! Cocktail Knight

Stressmen, ghastly monsters that originate from pent-up stress, relentlessly wreak havoc in Kirameki City. In response to the imminent threat these creatures pose, a group known as the Cocktail Knights—- four maidens with magical powers—is formed to defeat the stressmen. Although these heroines are admired by the entire population, only few know of their true identities. One such person is Riku Daichi, an ordinary high school boy who knows the identity of Valencia—one of the Cocktail Knights dubbed the Prince of Beauty. She is actually Sora Amagami, a cool cross-dressing girl and Riku's best friend.

Since Riku and Sora's classmates have yet to realize that Sora is a girl and a Cocktail Knight, Sora is unaware that her best friend knows her secret. However, there is something about Riku that Sora and their classmates are fully aware of: Riku's immense love for Valencia. Despite Riku constantly protecting the identity of his first love and best friend, Sora's actions toward Riku do not make things easier, with her blooming fondness for him making her secret more and more obvious!