Scoundrel - Scandalous Honey
[From ShoujoMagic]:
Aihara Shinobu is a high school student and lovely model. One day in Shibuya, she's handled roughly by a gang leader named Kyou, who insists he will make her his woman unless she can produce a boyfriend. Shinobu turns to her unrequited love, a true gentleman named Hibiki, the utter opposite of Kyou, and begs him to play the part. But what Shinobu doesn't realize is how long Kyou and Hibiki have waited for this moment...
WARNING: For mature audiences due to strong language.