Herluin Lothaire is a Breton merchant who sells alchemy supplies. He resides in The Ragged Flagon after completing the Thieves Guild's second "special job" to expand their influence to one of the other holds of Skyrim. This job is random and depends on the amount of work the Dragonborn has done in each hold. His shop is in an alcove just north of the entrance from the Ratway, along with Syndus, Arnskar Ember-Master, and Vanryth Gatharian.
- Weapons: Limited to daggers
- Potions: One of the more extensive lists of potions available found among merchants.
- Ingredients: Holds some of the more rare ingredients, such as Daedra Hearts, Fire Salts, and Void Salts.
- Books: Holds a larger inventory of recipes than most merchants.
- Misc: Limited to soul gems
- "Need some sort of toxin for a special occasion? That's where I come in."
- "I sell all sorts of poisons for almost every occasion."
- "So, name your poison! Ha ha ha. Oh, I never get tired of that one."
- Herluin is not allowed to invest on via the Investor perk under the Speech skill.
- Despite most of his dialogue being poison oriented, he carries more potions than poisons.
- There is a usable alchemy lab inside his shop.
- He seems to have Daedra Hearts more often than most alchemists.