A walker takes a shortcut across open fields at night, and something small and winged touches their face in the moonlight. That is the whole scene, and the poem is over almost before it begins. It is just three short lines, which suits the speed of the moment.
The speaker doesn't say what they feel, so the feeling has to be read from the details. "Shortcut" suggests an ordinary, slightly hurried walk, with no plan for anything special to happen. Then the touch interrupts it. A brush of wings is soft, quick and a little startling, and I'd guess it could be a bat or a moth, though the poem never says. Because the face is "moonlit," the speaker seems exposed and visible, as if the night were looking back.
The mood is quiet, delicate and slightly eerie, but not frightening. It feels like a brief, gentle meeting between a person and the wild dark.