Steps to reproduce
As user A, create a series with multiple works, then invite user B as co-creator on only one of the works.
As B, accept the creator invitation. B should now be a co-creator of the series, and of one work in the series.
As B, edit the co-created work in the series and choose "Remove Me As Author".
B is removed as co-creator of that work, but retains co-creator access to the series as a whole.
What should happen
B is removed as co-creator of that work, and as co-creator of the series as a whole.
This is similar to (co-creators are removed from all chapters but remain on the work).