Sex scenes relapse?

If you continued watching it: yes.
Be sensible.

 

No, unless you purposely watch the show for these scenes. Better to avoid it altogether in reboot, it might create cravings. It's not a relapse untill you deliberately watch it, going against your willpower. But if it is there by accident, like an advertisement in the streets, it doesnt reinforce anything. As a matter of fact. If it comes and you look away, it might strengthen your resolve a bit.

 

Note the difference between a reset and a relapse.

A reset is when you reset your counter, because you deliberately watched porn, or because you masturbated.

A relapse is the effect that it has on your brain, when your brain's healing is set backwards.

This means that you can have a reset without a relapse, and (in rare cases) a relapse without a reset.

What you did almost certainly isn't a relapse, because (given the circumstances) your brain almost certainly didn't go backwards in its healing.

Also, I agree with @TheRIghtChoise that you don't need to consider it as a reset.