Boku to Watashi no Juu-nen Koi

Tooru is a 5th grader who has always been in love with Nagisa, his next door neighbour who is a high school student. "I'll definitely get her to look at me." ..is what Tooru thinks but Nagisa only sees Tooru as a little brother. This is a frustrating yet charming story spanning over 10 years about two people with a five years age gap.