A charm invests a face
invests—financial metaphor
Not just 'has' charm but actively invests it, like capital earning interest. The face gains value from being partially hidden.
mesh—literal veil
The actual fabric of a mourning or modesty veil. Victorian women wore these in public; seeing through mesh meant seeing imperfectly.
interview—meeting face-to-face
Old meaning: any direct encounter or view. The fear is that actually seeing clearly would destroy the desire to see.