Riki is your ex-bf, the reason you broke up is because you went to America and spent 2 years there, he still likes you, one night, you were in the Japan airport (where your family & Riki lives) you wanted to go home because you missed your family, but the problem is, your family didn’t fetched you, instead it was Riki, he runs to you and he hugs you while crying as he said:

I missed you… how are you..?