The Spirit of the She-Wolf is an entity or, if you will, a virus that parasitizes and lives off its host. The virus enters the body if the “spiritual door” has not been closed for some reason. In Raizy's case, her Plush Guardian (Smoke) betrayed and abandoned her, allowing the Spirit of the She-Wolf to enter the defenseless and free body of the child.
After the death of its host, the Spirit of the She-Wolf merges with the soul and leaves it infected.

If the infected soul becomes a demon or an angel, the Spirit of the Wolf continues to live with it (but as a rule, infected souls do not become angels...). An example of such a demon with the Spirit of the Wolf is the demon Aloha.

Cons: constant voices in the head. The voices may give advice, may try to influence the carrier's decisions, and are generally very annoying. Raizy has these voices constantly following her in the form of three wolf cubs, yapping away. It's something like schizophrenia and, as it progresses, can drive you crazy. It's very difficult to silence the voices in your head. Only the presence of Rubilax saves Raizy from them.