tactical shagging
To engage in the activity of sex, not to enjoy it but to use said activity as a weapon to piss off your ex or to gain from it or to use tactics to gain sex from someone who would not normally have sex with you because it's morally wrong.
That's clearly just tactical shagging!
tactical shag
like a smoke break, but shagging instead
maurice, work is fucking me off, lets go for a quick tactical shag in the disabled toilets and get back to it.