Improve rubbing breasts in the vertical motion

The Hard version will be released in late December. I'll let you know the exact date as soon as it's decided. Thank you for your understanding.

The breasts shake during the vertical movement in XXX, but I found a fatal problem that the rubbing breasts and nipples action doesn't work correctly at this time.
So it requires to stop the breast shaking when in touching them, but especially in single-mode, the non-touching side of the breast should keep to shake normally. This is very difficult and I have to program it like through the eye of a needle.

But done.

Honestly, I made this part quite loosely in my previous work, but this time you should be able to handle it pretty rough. Alright, all the major bugs should now be fixed. Maybe, maybe..