Damn, I really do wanna see that second season now it looked like it'd be an awesome spinoff. Ah well.

For manga they have to end on a chapter that rounds out a complete volume for example, if they go over, if they're allowed to go over, they need to go over for an entire extra volume, like what happened with Dorohedoro.

I have quite a few series on my bookshelf where the last volume is notably thicker than the others because the ending chapter(s) doesn't fit neatly into a normal volume, there's no way this is a given practice.

The opposite can also be true. For example, Wotakoi has larger than usual manga volumes, both in page size and thickness, and the sixth and final one is noticeably smaller than the others because there's less in it.

Very good ending. Anything else as the mangaka say would lead to multiple volumes. So stop it just at the right moment where it can stop. The bottom line is, the protagonist can continue as a couple, in regardless of the situation. So stop it there. Rose can be honest about her job to Benika while Benika can accept Rose's work, which is a good compromise. Benika killing Rose will not necessarily help Benika and her father because they have already known too much secret.

The Gina-Hibei epilogue most likely was drawn so that it would complete a volume. Those two should have their own story and the mangaka can draw it without Rose, Benika, etc. A complete side story.

Everyone's always jumping to "axed" when they don't like an ending, even though this ending was basically locked in four chapters prior.

Well, there you go straight from the authors mouth: axed. I suspected as much, because it would take way more than four chapters to address everything they had been building up.

It's got to be tough being a mangaka. I can only imagine how much it hurts to spend time drawing up a grand story only for it to cancelled halfway through, not only killing your years of effort but also leading people to think your story (and you yourself) suck.

The author meant Hibai's and Gina's story.

More gay girls with guns like this would be awesome