Pull finger?

In a variation of the technique, the pulling-off finger is dragged slightly across the face of the string while performing the pull-off. This results in the string being gently sounded, either by the player's finger callus or by their fretting-finger fingernail. This increases the volume and sustain of the pulled-off note, although the sound of the fretting finger dragging over the string may be audible on both an amplified instrument and on a brightly-strung acoustic instrument.