A person would literally have to be demonic to defend late-term abortion, so I won't explore that.
But I will say that I find it important that libertarians slam away at limiting government intervention in a variety of areas. Personally, I think gay marriage is one of these - it is a complete snow job over the huge pink elephant in the living room of government involvement in marriage at all. Marriage is spiritual, religious, based on love, private and has zero relevence to government authorization. It is the grossest of all boundary oversteps for the government to "license" a marriage, and it needs to stop.
I also think that there is a whole area of personal privacy rights that extend into healthcare, taxation, child raising and other areas that also include sexual rights which, if properly followed, would protect private adult sexuality of whatever kind while denying any special rights or hate crimes. But the baby's thrown out with the bathwater on that, too.
Just saying, as examples.
I just don't see two sodomites that way and no society in history has either until the post 20th century collapse of western civilization but if you think that America has so declined and distanced ourselves from our roots, then support the party of "demons".