Just read this chapter again for no particular reason then suddenly had the urge to look for more Futanari-Hyuuga stories. I was especially focused on trying to find stories where Hinata and Hanabi go at it and one of them is Futa. Sad to say I didn't find all that much but, I did find a site with an old RPG that has a Futa-Hanabi jump her sister Hinata and attempt to screw her into submission. To bad the writers don't seem to be planning to continue it... Any way, look forward to seeing the next chapter as I always give this story a quick check everyday to see if has been updated. Also hope to see your Ninja Gate story get updated soon.
Ps: the site with the RP is http://bluemoonroleplaying.com/forums/showthread.php?tid=24041