Maybe it's because I'm reading the English translations (of which I have read 1 - 5), but I think this series is a lot of fun. I'm not a fan of the forced sexual situations, but the Semes never seem to go too far, and our Ukes are constantly shown taking care of themselves with other people, so I'm thinking the mangaka intends for us to understand that the Ukes are just letting the Semes think they're in charge.
Overall, the tone of the series is light-hearted, with ridiculous situations and plenty of humour. Occasionally, the emotional reaction of some of the characters can be intense in the extreme, and I admit, I would like these emotions and reactions explored more fully and in seriousness sometimes - that's why I rated this series an 8 instead of a 10. But I think the series is meant to be a humourous romp, which is probably why those intense moments aren't taken more seriously.
As I read on, I found myself giggling out-loud several times, something I don't normally do. I'm an older reader as well, so "giggle" is far from my default setting. No series has come close to reminding me of Gravitation until now, but Our Kingdom certainly has the right flavour, although far more sanity. ~_^
I'm looking forward to more volumes in English, but if they never happen, I hope someone will pick up scanlating this series again! <3