@mammon
Eh, it could be what they feel the most comfortable dressed in. To them, it may not be seen as "thot-y" because it is what they would wear to go out for "food", meet people (also food), dress casually, etc.. Remember that business formal to them is basically naked. Also, succubi often have wings and a tail, which make most clothing options difficult to simply impossible to wear comfortably or without ripping it. So the more shown skin, the less chance there is to ruin the cloths. Plus the easier it is to remove it when they go to "eat".