The Blessings of Maa Baglamukhi develop a divine protective defend in the shape of the aura close to someone thus shielding him/her from malefic energies in the shape of black magic spells or evil eye. A different etymology indicates that valga means "to paralyze" and symbolizes the strength of stambhana, https://www.youtube.com/shorts/5VeSyP9JRw0