[asaqe]

Originally Posted by raidou

I always thought the human form is the temporary one, considering they were created based on animals and return to that form once the master died or too weak(just like the twins).

Spoiler:

Maybe not since Subaru were called type 0 and those tubes was labeled V and XI? (cant remember exact number)

They could possibly been an earlier experiment but again I am running into another roadblock.