AITA for telling my roommate's demon to "get a job" during its possession attempt?

Okay so I (26F) know how this is going to sound. Bear with me.

My roommate Derek (24M) has been acting weird for about three weeks. I'm not talking "leaving dishes in the sink" weird. I'm talking "floating six inches off the ground while whispering in Latin" weird. I've lived with Derek for two years and he has always been a reasonable guy, so I gave him the benefit of the doubt for as long as I could. We all have our months.

Last Tuesday I came home from a double shift and Derek was in the kitchen with the lights off. He was standing completely still facing the wall, and when he turned around his eyes were fully black. I said "hey Derek" and he said, in this deep grinding voice that was definitely not Derek's, "I am Vorrathex, Devourer of Souls, and I have come to—"

And here's where I might be the asshole.

I interrupted him and said: "Sorry, can this wait? I just got off a double. Also, if you're going to be possessing Derek full-time now, you need to figure out his half of the rent."

The demon stopped and stared at me. I asked if he had any references or prior work history because the landlord does credit checks and Derek's name is on the lease. Vorrathex said, and I quote, "Mortals do not speak to me of credit checks." I told him that was exactly the kind of attitude that was going to make the apartment search really hard for him.

He left. Like, just left. Derek collapsed, totally fine, no memory of anything. I gave Derek some Gatorade and didn't bring it up because honestly what do you even say.

The thing is, my friend Kayla thinks I was rude. She says demons are beings of immense ancient power and I should have shown more respect, or at least let him finish his speech before shutting him down. She says I "dismissed his whole thing" and that it was condescending. She might have a point. He did seem genuinely thrown off, and I didn't really give him a chance to explain what he wanted.

But also he was going to devour my soul, probably. I feel like the bar for politeness lowers a bit in that situation.

For context: Derek is fine. He has no memory of the past three weeks and thinks he had mono. I haven't told him because I don't know how to start that conversation. Kayla thinks I owe Vorrathex an apology. I think Kayla needs to mind her business. But then again, she might be right.

AITA?

Edit: Yes I know I should tell Derek. I'm working up to it. He's very sensitive about the mono thing because he thinks he got it from his ex and it's complicated.

Edit 2: Vorrathex has returned. He slid a piece of paper under my door that appears to be a CV. His last position was "Eternal Tormentor" at a company called "The Abyss." He lists "soul extraction," "dread inducement," and "Microsoft Excel" as skills. I don't know what to do with this information.

Edit 3: I asked if he had references. He said yes. The references are "other demons." I told him that might not fly with the landlord. He said he would "consider this feedback." Derek is asleep and does not know any of this is happening.