I'm used to being unwanted, Kurusu, if you haven't forgotten. It isn't an unwelcome reminder to me that the world turns without paying me any mind. [He's-- frustrated. Akira is frustrating. He wants to care for him and pay attention to him and he doesn't want to "move on without him", but he's not taking into consideration that he may want to be forgotten. All he wanted for years was to be seen, for someone to recognize what he did, and now the idea is soured in his heart and his mind because he had it, he had the attention of all of Japan and some of the whole world, but it was all a lie. It was fake, and he was setting himself up.]

[So he thinks he's allotted some time to be forgotten. Or maybe he'd just like to forget himself.]