Kanpeki Kareshi Kanojo

From HaruHime:
A perfect boyfriend that loves Kin erasers and big boobs.
A perfect girlfriend that is average-looking and flat-chested.
Cry, laugh and squeal, because this is a story of passion and unrequited love!
Although Natsu, 16, thought that Ichijou was the perfect boyfriend, it turns out it was only her illusion. When she confesses her feelings for Ichijou only to get the reply “I want a cuter girl than you,” she discovers that what he’s really interested in is Kin erasers and big boobs. Despite Natsu’s disappointment, she still finds herself being drawn to Ichijou more by the day. Where could a loving young lady possibly direct this passion of hers!?