Well that was a surprisingly sweet ending.  Nice to that despite the giantesses being very prideful and thinking little of Jack, Ulga honored her promise.  Plus all those guards cheering when the curse was announced to be broken was pretty cute.  Mythia actually seemed to be a little fond of Jack at the end there but then she was a bit more concerned for his well being than Ulga or the daughters.  And nice to see Aria and Alice trying to make amends with Jack after what they put him through.

Overall, this was a delightfully lewd story with dominance and some heartwarming parts.  I normally don't like futa but my brain seems to make an exception at times and this was one of them.  The giantesses and their realm was fun.  It's fun how they were all these incredibly voluptuous, casually lewd beings and thought of Jack as a puny plaything most of the time despite his importance to their race.  The daughters got carried away with the playing bit but everything worked out in the end, to Jack's relief.

As for a "what if the giantesses found a way to human world" scenario/sequal, I'm certainly going to be thinking about that.  A good setting always gets my "what if" juices flowing.