No, Waiting is a stand-alone story, rather than part of a series.

The ending is ambiguous, but that’s intentional, to give readers an opportunity to imagine what exactly happens next. As for missing it, I reckon there’s quite a few gems written years ago that newcomers might not have seen, so I plan to occasionally repost older stories to my feed. Look out for them.

And if you haven’t read Waiting yet, you should report to detention