Angel actually wanted to ask this question for quite some time.
Borrowing a body for rebirth, also known as possession. This exists in the Wizards' Realm as well. For instance, the "Little Demon" Glarke from Dusknights' Blade once borrowed the body of a recently deceased person for rebirth with Sanders' help. He now goes by the name Spiwey and serves under Flora.
Additionally, Greya lost her body in the Nightmare Realm and had to find a young girl's body to temporarily parasite her consciousness.
Both situations count as borrowing a body for rebirth, but Glarke completely changed his identity; whereas Greya did not harm the girl's consciousness and merely parasited. When she retrieves her body, the girl can resume her own life.
Although possession exists in the Wizards' Realm, it's not common. The reason is easy to understand: because possession only makes you weaken, without any major change.
