My Reply to you Plot reveal (Spoilers ahead, you were warned):
You don't lose your stats, you're submerged in a fake reality, something like a Matrix. The monster and you "died" but surprise, you didn't.
(Ok fair enough. Actually, an interesting story element.)
The monster, stronger than you created that reality were you're trapped, because, as you stated, you can reboot, but only when you die, so he can't really kill you.
(If he created this reality, then you are trapped in it with the god that created it. He can do anything he wants, whenever he wants. Afterall, what's to stop him from resetting reality and changing the rules as you go?)
That's why your stats are zero at the very beginning. MC didn't reboot, the big ugly monster tweeked his reality to make you think you're powerless. It's a porn game plot twist, don't expect nothing that deep or logic.
(It seems I’m taking this AVN more seriously than you are! That’s not a good thing for you.)
(There’s an old saying: Perception is reality. Meaning if the MC thinks he is weak, then he really is weak. Knowing that it’s a dream I find myself wondering why the Big Bad has held back at all!)
(He has you trapped in a dream that not even death can save you from, he could torture you into insanity and beyond, allowing you to die and then reset reality every so often. You would end up wishing you could die!)