A quick and painless execution for the secondary love interest. It was done in such a subdued way, I hardly noticed it. Some of the most interesting parts of this chapter were the ones about the society. I'm kind of interested just how much worldbuilding there will be done.
Lastly the happiest moment was on the extra page, which said that the collar is going to be put away. That was always the part which weirded me out. Especially since Mels collar was so bulky and such a strong reminder of the master/slave relationship. Well, almost all is good now and I sincerely hope that there won't be any unncessary drama with family/outsiders trying to meddle.
Edit:
@Kisato
This is an onee/loli manga. The age gap is its theme. Plus you're 16 chapters in, you should've noticed that by now. What I found much iffyer was the rather clear indication that they're supposed to be master/slave (as I already outlined)