@EmMac1066 Hi! I just wanted to add a couple things to @PoptartJuniper 's and @xochiquetzl_xkvn 's suggestions. Vampires can be eliminated manually through Manage Worlds / Manage Households. The Vampire pack adds the Forgotten Hollow world, which is inhabited by the premade vampires; Count Vladislaus Straud IV and the siblings Lillith and Caleb Vatore. You have the option to eliminate these right away, if you wish. Also, in my experience, the only one that will attempt to bite your played sims is Vladislaus. As Poptart mentioned, you can lock your door to trespassers to prevent other vampires from intruding. As for other game-generated vampires, you will only notice them if they fly as a bat (some can run really fast but I haven't noticed it for NPC sims other than Caleb and Lillith) or make their hissing noises. If you do notice them, just make a note of their name, look for them in Manage Househoulds, and delete them. Without a mod, as xochiquetzl mentioned, there's no way to prevent them from appearing in the game. However, after deleting Vladislaus, Lillith and Caleb, the chances of seeing others is limited I think.
As for the Realm of Magic pack, if you never take your sims to the Magic Realm or have them become spellcasters, you'll never even notice the spellcaster sims. Those NPCs do not do magic outside the Magic Realm, which is a semi-secret area that you can only travel to through a somewhat hidden portal or as a spellcaster. Hope this helps!
Edit: BTW I love the clothing and build items too! :-)
What @JonaO703 said. Caleb and Lilith come knock on your door, but if you let them in they'll chat with you and then use your computer or watch your television, lol. :D They don't sneak into your house or try to bite your Sims; Caleb has the "Good Vampire" aspiration that's all about not biting people. (Er. He's one of my favorite Sims, TBH, so you could cure him or use one of the mods I mentioned to turn him into a human if you didn't want to delete him, although it's your game and that's absolutely an option.)
Vladislaus will try to bite your Sims, but he hates witnesses. He'll leave if anyone is awake and in the area. When the pack was first released he would break into your house, then he stopped for the longest time, and now he's started again. It's honestly more of a nuisance, though; he doesn't kill anyone. He drinks blood, leaves the victim passed out on the floor, and leaves, and the victim wakes up tired and with a sore neck. My tent-dwelling Sim had no door to lock, so i had her just be nice to him and he left her alone and even called her and invited her over to offer to turn her into a vampire (she declined; she's all about that outdoorsy life). So even Vlad isn't that scary.
I digress, though. You don't want vampires in your game. I've had random vampires spawn, so I would probably use a mod to be sure.
