From Chibi Manga:
Yui secretely admires the smart Shinohara-kun and puts all her effort into studying to be a good match for him. Then one day she overhears him talking to his friends saying that he would only want a girlfriend who is more stupid than himself. Arima-kun sees her crying and helps her and feelings arise. but when Yui's mother finds out, she tells Yui that she must stay away from Arima-kun.