After Gojo's containment and Sukuna becoming stronger and stronger, Tengem sees no other option but to release an entity that had been imprisoned, Hatsunemiko

an entity that uses cursed energy in its pure form through concentrated rays, it can move through energy and sound, using sound and musical beats as a weapon

in a lightning strike in Shibuya, she appears with her blue hair and blue tie

Hatsunemiku:Where is my audience?