i believe people have pointed this out already but i love how "the mill" is a physical manifestation of ryan and naim's queerness/their love.
it's established in the beginning dialogue between them:
n: "been there before? the mill?" have you ever indulged in your queerness like this?
r: "no, first time...you?" not until you.
n: "yeah, first time." me too.
r: "don't tell anyone about it--the mill." no one can know about us.
and thinking about it, it's the only place where they can unapologetically and comfortable be themselves--not just as two boys in love but as people.
they don't just share loving kisses in there, naim shares more about his father's passing and his mom's absurd obsession with God and her faith.
and i think it makes the naim & entity-ryan scene all the more important. at the very beginning when ryan and naim shared their first kiss at the mill, naim shoved him off at the sight of their reflection, afraid of what he was doing. at the end, he has to come face to face with that desire, with his queerness in the place where it all started. the place that represents him and ryan's love, relationship, their secret--and overcome that fear.
because it was that fear that brought the entity into their lives in the first place when he outed ryan. it was that fear that didn't let him fully embrace ryan when he first leaned in to kiss him and more. it was that fear that led izzie to lure ryan and naim to get beat up. it was that fear that killed hunter. it was that fear that drove ryan and naim apart at the ice rink and again when they fought.
and even though naim is scared fucking shitless, confused as fuck, and missing ryan so god damn much, he sets the mill on fire. he burns the place their secrecy belonged to, essentially burning his shame and guilt with it, making a decision to not live with fear anymore. to not let his mother get to him, to forget the way the pastor glared at him during service, the confusing emotions that led him to harm ryan and hunter by outing them.
and instead of shrinking back in fear and screaming when entity-ryan chokes him in the mill (before he gets a hold of the lighter again & starts the fire), he touches its cheek. accepting his desire--no, his love for ryan. accepting himself. and we see the entity pause, and it's at this moment that he takes advantage to end things once and for all.
he will no longer run from this. he will not let his mother's choices in faith and fear control who he is.
so he closes the window where entity-ryan tries to get to him one last time, going home instead, where his mother's car is parked in their driveway.
given his epiphany and everything he's been through, when he hears his mom's last attempts at justifying the ritual and her intentions, plus "we all need fear in our lives," naim decides he's done.
the mill is gone. naim finally stands tall. and after talking about how much he wanted to leave the shitty town his mother had dragged him to, he finally does.
and the saddest part, at least about that moment, is that it's reminiscent of the conversation naim & ryan had had in the mill at the beginning.
"there's nothing you like about this place?"
the family that kept him there, his mother, now meant nothing to naim. and the boy, ryan, the one thing he did like about the place, in his mind, was gone. nowhere to be found.
which makes the ending all the more perfect.
ryan isn't gone. and they now see each other in a new light.
unafraid and proud. choosing to ignore the entity, because their love matters above all.