Ai mo Kawarazu

Iinishi is a popular high school boy, but because he doesn't understand romantic feelings, he has never been in love with the other sex. Still, though he lacks for nothing, he is pestered by the girls around him. Then he meets a girl in his class named Riru, who bluntly tells him she doesn't have any feelings of love either, and, thinking they resemble each other, they quickly become close...!?

(Source: Kodansha, translated)