Time. The game measures time in increments of two in game hours (15 seconds). When you start the game you essentially start at dawn. Then the completes two hours every 15 seconds, so it takes about a minute and a half to rotate to night, though you will only see the effect outside. There is one catch though that I haven't been able to solve. Moving to a new map does restart the 15 second timer, so if you jump between locations a bunch it could halt that progress.
Viewing post in Dom/Minion 6.0 Forests and Fairytales comments
Gotcha. I can for sure say there is more chastity content in the works. As far as Dom with another sub, that will also show up a bit more, though the degree to which that fits your taste will depend a bit. If you are specifically into the strict spectating aspect, I probably wouldn't say that will come up as often. Occasionally, yes, but not super often. If it's just preestablished Doms with other subs, then that will be more frequent.