Depends on the fandom, I think. I've found some H/C in the NCIS fandom (which is the one I'm binging on right now) that lead to relationship but the sex part doesn't come till more toward the end.. and there's enough plot in the story that it doesn't count as PWP. There's even some that don't have romantic relationships and actually focus on family-type relationships instead :O

'-' Then again that show has had people getting blown up, shot, infected with the pneumonic plague, kidnapped, etc etc so it might not be that much of a stretch for the fans XD;;;;; And the team is considered one, big dysfunctional family in-show. *shrug*

..They like to call it "whump" too XDD I dunno if that's a normal non-anime thing (like how it's slash instead of yaoi or yuri) but MAN it makes me giggle.