Demi-Hollows
The Demi-Hollow (半虚 (デミ・ホロウ, demi-horō?) is an Jukaburei that is evolving into a Hollow. It usually takes a while to a Demi-Hollow to evolve into a Hollow yet it can be sped up if the hole in their chest is forcefully opened.
Read more about this topic: Noitora