Shouki no Sata Day Night

Hajime Hime, the leader of the Pussycats gang, tried to show his friends how to pick up girls by talking to a pony-tailed high school girl in a sailor suit uniform. But to his surprise, he got turned down. Despite the pain of rejection, Hajime fell in love at first sight, and with the help of his friends, he set out to find that girl. He managed to find her, but it turned out that she was a young lady known for her fighting skill...?

(Source: BookWalker, translated)

Note: Date based on the release of the tankoubon.