This is as far as the raws go. The next chapter (the last chapter) is to be published at the end of the month.
If you feel confused about that, like you feel that there's clearly a lot more the author planned to do with the story, don't worry, you're not alone.
As I understand it, the magazine this manga was being published in folded. It, and several other series, were moved to a sister publication, but this one was only given a couple more chapters to wrap up with.
If anyone has any reason to believe there's more to it, I'd be interested in seeing proof of such.
I'll try to translate the last chapter as soon as I can, but that mostly depends on when the raw will be uploaded.
That all being said, this is it for now. If you've followed all 15 chapters, I want you to know I appreciate it, and I hope you've been able to enjoy the read.