If you're looking for manga similar to The Miracles of the Namiya General Store (Novel), you might like these titles.
Ninagawa Mio is a tough biker-gang "yankee" girl. One day, while rescuing a child from an oncoming bus, she accidentally crashes her motorbike into a very expensive car. To make up for it, the owner Saga demands she come to meet him alone. Mio has no idea what to expect at this meeting, and is bewildered when she finds herself entered into some contest called "Dorukon."
I suddenly remembered. This world is the world of an erotic manga, and that I was reincarnated as the scumbag who is supposed to steal the heroine in this world. Well, I don't have such a hobby, so I thought the heroine should get along with the protagonist. But why are you paying attention to me, heroine?