I've been told that by many females, and they always reveal it after getting to know me, etc.
It usually goes something like,"yeah I used to always notice you but I never said anything because I was always intimidated by you."
I ask why, and they usually say something to the effect of it being the way I look (mean) and the way I carry myself (very no-nonsense and serious).
It's just the way I am.
And I've found that while it's very appealing to women, it's also intimidating at the same time