The award-winning series known as Bokura ga Ita in Japan! Nanami Takahashi falls for Motoharu Yano, the most popular, carefree boy in class. For Nanami, it's first love, but Yano is still grieving the death of his girlfriend who died the year before. Don't regret. Do everything you can while you still have the chance. That's what I think it means... ...to have a "happy heart."