He has gruff and impatient mannerisms. He tends to keep to himself when he is not at his stall in the market.
During the Daedric quest "The Taste of Death," it is revealed that he, along with a few other citizens of Markarth, is a cannibal. He implies that he sells human flesh at his shop if talked to at the feast in The Taste of Death, however this may just be a macabre joke as human flesh can never be bought from his stall, even by a cannibal.
Degaine: "Alms. Give me some meat, you fat Nord!"
Hogni Red-Arm: "What did you say to me, Reachman?"
Degaine: "I said give me some meat. I'm hungry, and the Divines know you don't need more food in that huge gut of yours."
Hogni: "You little twig. I'll snap you in two!"
Degaine: "Just try it. Maybe a little time inside Cidhna Mine will get rid of all that fat on you."
Hogni: "Look at you, begging on the streets. Learn a trade."
Degaine: "Picking on me again, you backbiting Nord? Tired of those prissy nobles turning down your rotten slabs of venison?"
Hogni: "How dare you. No one turns down cut meat from Hogni Red-Arm!"
Degaine: "Hogni Red-Arm, more like Hogni Fat-Arm."
Hogni: "You there, pretty lady. You need some fresh meat for your family? Just look at the blood coming from this cut...."
Hroki: "That's disgusting, get that rotting carcass away from me!"
Hogni: "What's wrong? You have to look at the blood closely to see the quality of the meat. How else will you know it's fresh?"
Hroki: "I don't need to know if it's fresh from this distance."
Hroki: "Ugh. You're the most disgusting merchant I have ever seen. The guards should take you away."
Hogni: "The only people I offend are cheats who don't pay me enough gold coin, or idiots who don't know good meat when I throw it at their faces."
Hroki: If you ever think of throwing meat at me, I will have you dragged off to Cidhna Mine so fast the guards will yank those filthy arms of yours off."
Hogni: "What do I do to deserve such hatred? You give people good food and good prices, and all they do is insult you."
- "Hey you. Yeah, you. Fresh meat for your stomach."
- "The bloodiest beef in the Reach."
- "You want a cut of venison or mutton? Of course you do."
- "Don't try to haggle with me. Buy or leave."
- "A man like me makes a lot of enemies. People are always trying to cheat me."
- "I paid extra for the biggest room in the Silver-Blood Inn. I need space to stretch these arms."
- (After the end of No One Escapes Cidhna Mine is completed by siding with Thonar Silver-Blood) "Can't believe anyone was dumb enough to mistake you for a Forsworn agent."
- (After the end of No One Escapes Cidhna Mine is completed by siding with Madanach) "Huh. Heard you broke out of Cidhna Mine with those Forsworn. Do you have any idea how many died?"
- If he and the other Namira cannibals are killed, he will be the only merchant who receives no replacement at his stall.
- At the feast, He tells Lisbet that his favorite part of the body is the liver. He goes on to say that his brother's liver was juicy.
- While he offers mutton in his patter at his stand, he never has any. (It would have to be imported from Cyrodiil as there are no known, if any, sheep in Skyrim.)