Short story!
They call him "Star Boy." Mainly because his head is always way up in the stars, yet he's invisible to most people. They don't notice when he's faded out. He's very quiet, and keeps these walls built up around him because he finds it difficult to trust anyone. This is the boy Katsuki is completely, and undeniably in love with. He wants to show Star Biy how he feels, but is scared of his reaction. He is utterly oblivious to Star Boy's demeanor when he is around the blonde. Will these two finally come together with their one and only shot, or will they blow it?
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"And yet, here you are, pining after me. The one person no one seems to notice."
"You really are oblivious, aren't you?"