Veil
Veiled anime characters have many styles. This tag probably conjures up a wedding. We love seeing our favorite waifus in wedding dresses with sheer veils over their hair in anime. Not just for wedding scenes. Nuns, dancers with masks, and mysterious fantasy characters trying to hide from the main characters may also use this tag.
How the artist works with fabric makes a veil look good. The best fanart shows how translucent the material is. The character's eyes and face are barely visible through lace or silk. Dark mourning veils can make a picture sad and dramatic. Dancers' face veils with shiny headpieces look sexy. Light passing through sheer fabric creates cool art effects.
The classic bride look is still the most common use for this accessory. Gacha games always release wedding-themed character outfits, so bridal fanart will always be beautiful. A character blushing behind white tulle before the veil-lifting scene is romantic. A veil, whether it covers the face or the back of the head, gives any character design elegance and mystery.