Sexcalation is the process by which sexual tension keeps escalating between two people who insist they are “Just friends” to the point where shenanigans are inevitable. The unique quality of sexcalatory situations is that the principal imbeciles are in total denial of the mechanisms at work and hence appear completely oblivious to it.
James: I thought they were just friends!
Jill: Yeah but very soon it sexcalated into something more than that.
Mary: Honestly, everyone knew they liked each other, sexcalation was inevitable.