In a poll of Skyrim's most annoying NPCs I suspect Nazeem the walking meme would score pretty high ("Do you get to the Cloud District very often?"), along with Cicero the jester, Whiterun's shouty god-botherer Heimskr, and that one kid in Solitude who says, "I thought adventurers were supposed to look tough?" Spare a hateful thought for Belethor though, the sleazy owner of Belethor's General Goods in Whiterun, who condescendingly says, "Dooo come back," when you leave his store.
Belethor also says, "Everything's for sale my friend. Everything. If I had a sister I'd sell her in a second." That seems to have given prolific modder wSkeever an idea. Belethor's Sister is a quest mod for Skyrim Special Edition that reveals the pawnbroker really does have a sister, named Lelaegh, and he really did sell her. Your job is to track Lelaegh down, rescue her, and then help her take control of her deadbeat brother's shop.
Finding Lelaegh isn't easy. The trail of people who have bought and sold her leads through various existing merchant NPCs and dungeons until finally you have to travel to the Soul Cairn from the Dawnguard DLC, which means you'll need to do a chunk of that questline or be willing to use Skyrim's console commands ("coc DLC01SoulCairnOrigin" will teleport you there direct).
Finally, helping Lelaegh take over Belethor's General Goods requires dealing with Whiterun merchants who own shares in it like, yes, Nazeem. (If you've already killed him in your playthrough, that might be a problem.) Once you do, you'll be able to take joint ownership of the shop, which will result in weekly payouts as well as a series of radiant quests to help Lelaegh get the business booming.
While there are plenty of quest mods that add things to Skyrim inspired by pop culture, from Dark Souls to Doctor Who, Belethor's Sister is the kind that draws on Skyrim itself. It's like fanfic that spots a loose thread nobody else realized was even dangling and then pulls on it. The end result builds on the personality of characters we've already met, deepening our enjoyment of the original. Before this I couldn't even have told you who Belethor was off the top of my head, just another of too many shady characters voiced by Stephen Russell, but now he'll forever be that guy whose sister I went on an epic journey to find.
Belethor's Sister is another mod that makes use of AI trained on existing dialogue to add lines to NPCs, and it works pretty well. Maybe it helps that Skyrim reuses the same actors for so many characters, providing a wealth of material to draw on.
You can download Belethor's Sister for Skyrim Special Edition on Nexus Mods. You'll need to be at least level 20 to begin the quest, so if you're starting a fresh player-character I recommend You Are Not a Novice – Higher Level Start to begin as a more experienced Dragonborn. And then you can round it out with some more of the best Skyrim Special Edition mods.
Dooo come back.