u/R_ainia

I read this book a long time ago, and I’ve forgotten almost everything about the plot. I read the English version.
All I can remember is that the protagonist was possibly a boy living on a spaceship or on the Moon. On the spaceship, he met someone (possibly a girl) whom only he could see. The book also specifically described this girl’s eyes as being blue. Does anyone happen to know what book this might be based on this information? I know the details are very limited, and I’m sorry about that.