Pretty sure there's a bug in this case... since I been doing non-sex interaction at least over a hundred times. Often 3 times in a row for the same character in one day and multiple days in a row. It always give +5 action turns.
There also doesn't seem to be a check to make a character refuse intimacy since I can literally have a newly enslaved character accept my intimacy proposal on the first try where both their obedience and loyalty are in the red zone.