Not all Daedra are evil. Most don't even care about us, except what we can do for them, which they reward us greatly for. I encountered 2 Vigilants of Stendarr at Meridia's Shrine, and slew them instantly. Meridia is a good Daedra. She is practically the same thing as the Vigilants of Stendarr. Azura is typically considered good, except in Skyrim she is depicted more...vengeful. Peryite could be considered good, as his sphere is essentially justice. Malacath is essentially an abolitionist. Sanguine and Sheogorath just want to have a good time. The only ones you could truly call "bad Daedra" are Molag Bal and Mehrunes Dagon. The others are for the most part, neutral/good.
And yes, I hate the Vigilants of Stendarr. They're as bloodthirsty as the things they hunt, sometimes more so. When they eradicate all other monsters from Tamriel, they will still have themselves to kill.
Ehh.. not really.
If I make people kill eachother and and upset a whole bunch of people for my own good. Just to have a laugh make me a good person, just wanting to habe fun!
all deadra are extremly selfish and would not mind having mortals die for their petty tasks. Sure if they manage to compleat the job they get a nice reward. Though that isnt really hard for a deadra price to conjure up. All are bad, just more or less. You will learn this if you read a bunch of lore on the deadra related tings such as books

Edit: sorry for spelling.. (Phone

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