Putting aside how she's completely not interested, he's disrespectful to her station, and he's been informing on her since they met - did everyone forget why he was exiled from Westeros? If so, here: it was for selling people into slavery, what. And lest anyone go thinking he was taking extreme measure for extreme crimes, the people in question were poachers. They went hunting on the wrong land, and Jorah sold them to Seven-knows-where so he could earn a buck to pamper his pouty lady.
And don't assume he's repentant, either. When Dany can't bear to see her people raping the women of the conquered tribe, Jorah's sympathy and obedience kicks in only after he first reacts with confusion. Two books later he's counseling her to invest in slaves of her own.
I understand how irresistible it is to see a man picking up a fainting woman in his arms, but beyond that, ugh. Dany hasn't had a worthy love interest yet. She doesn't need one.