I've Fallen in Love with an Alien

Tomonaga Kairi is the top student in his year and and a skeptic when it comes to the universe. But one day, he accidentally gets involved with the eccentric Nanbu-senpai, president and the only member of the Space Research Club. What will happen to Tomonaga when she tries to get him to join her club before it gets abolished..!? (Source: ShoujoHearts)