The blessings of Maa Baglamukhi make a divine protective shield in the form of the aura around someone thus preserving him/her from malefic energies in the shape of black magic spells or evil eye. Yet another etymology implies that valga means "to paralyze" and symbolizes the power of stambhana, https://saraswati-mantra-for-know87422.smblogsites.com/32651936/about-baglamukhi