Futari to 5-nin

Osamu Hiratake is a junior high school boy who confessed to a girl at school and was totally rejected. In order to learn how to be popular, Osamu treats his "philosophical senpai" to ramen and tries to discuss it at their boarding house. Then out his window, he saw a beautiful girl move in next door. Osamu falls in love with the beautiful girl at first sight. However, it turns out there are five girls, and all of them looked exactly the same...

(Source: Wikipedia, translated)