This is a Fred Weasley and Hermione Granger fanfic. Sixth book.
Hermione is angry that Ron doesn't love her like she loves him, and is heart broken that he is with Lavender Brown. Fred Weasley knows how she is feeling, and hates Lavender and wants his younger brother to date a girl like Hermione. So together they devise a plan to make Ron see Hermione in the right light.
Yet, they end up with an outcome neither of them ever expected.