I'm the face in your dreams of glass

from Smashing Pumpkins – Zero Lyrics on Rap Genius

Meaning

Glass is see through (unlike a mirror) so to be the face on the other side of glass would be to always be there for the person or maybe not for them, but simply following them.

The perfect person you never bother to notice.

To help improve the meaning of these lyrics, visit “Zero” by Smashing Pumpkins Lyrics and leave a comment on the lyrics box