Zangetsu becomes an enemy, indeed. He said he is sick and tired of living in Ichigo's head LOL (after the end credits).
There are many interesing facts about Zanpakutou
- They have their own soul.
- They have their own wills.
- Disturbingly, they desired this rebellion
This is the most interesting Bleach anime filler. There are more fights in store so look forward to the next episode G.w.