I've understood Tim and Cassie didn't sleep together in New52 Teen Titans. The last issue of New52 Teen Titans implied they just kissed.
Also, it seems lobdell confirmed it was just a kiss.
So, even if "everything happened", Tim and Cassie never sleep together.
However, even if the story doesn't dwell on that, that means Clark still had a regular girl as a sex toy.
That's why I just prefer to believe that never happened. I suspect DC also prefer this even when they say "everything happened".