If he's given a gold coin, he becomes a candidate for marriage. Additionally, if he dies after given a coin, in his will he says that he and the Dragonborn are related. The Jarl of Windhelm will then give you a condolence letter and an inheritance of 100 gold. If you do not approach the Jarl of Windhelm, a courier will find you and hand you a letter as well as the inheritance. It is also possible to marry him if you allow him to keep a dropped article of clothing or piece of armor.
Upon downloading and activating the Unofficial Skyrim Patch, Aventus Aretino will leave the Aretino Residence and Angrenor will move in. His dialogue upon moving in is that he has been close to the Aretino family and he feels that they wouldn't mind if he moves in. He also states that he doesn't believe the rumor that Aventus called an assassin to the home. The spot where Aventus performed the black sacrament also has been cleaned up, though the house is still a mess.
PC 360 PS3 After dropping an item anywhere in Windhelm, he shows up with it and asks you if he can keep it.
He is the Stormcloak counterpart of Noster Eagle-Eye. Both fought in the Great War, claim to have been the best at what they did, lost everything due to injury, and are beggars in the capital cities of the Imperials and Stormcloaks during the civil war.
Despite his disliking of the Dark Elves, unlike Rolff Stone-Fist, he doesn't insult player's race if they're a Dunmer.
One of his quotes possibly references the line made by many city guards. "I use to be an adventurer like you, until I took an arrow to the knee."
When you marry him he will still ask for some gold.
He is the only Beggar who is able to be married in the game.