Being unaware of their own hotness.
When a hot person is oblivious to how much they could get laid if they just tried a little harder, it's an immediate panty-dropper. And guys aware of it are the worst. Five o'clock shadow.
Personal preference, but the light scruff gets me every time. A nice low voice. Not like, Barry White or anything, but a rich baritone can make someone's less attractive traits vanish in a second.
7 Guys Share What Makes Them Feel Sexy
I've developed crushes on just voices before. Ability to banter. There is nothing worse than being witty in the general direction of a human brick wall. This actually makes hot guys instantly less aunty nude movies. Physical gentleness during sex.