Miss

From JShoujo Scans:

Falling in love with him was her biggest mistake... After being badly bullied in junior high, Kazu's sworn off getting deeply involved with other people. One day though, the resident class playboy, Kirishima, comes and tears down the walls she's built around her heart. She finds herself falling quick and hard...but is she only setting herself up for heartbreak?!

Volume 02 contains the oneshot "Key Point"