Reclaim Sex is what you call sex with your regular partner when one of you has hurt the other by having sex with someone else. It means to reclaim the feelings between you in the relationship. Similar to Makeup Sex.
I thought I'd be OK with Joey banging that hoe from the bar, but it got to me and really needed some Reclaim Sex when he came home at 3 am with the lipstick and beer and sex sweat smell all over him.