Interesting. My first response would be that this character essentially models a real-life person, which IMHO can't be mapped out correctly by the D&D alignment system. But that's not terribly useful, so let's look at it as D&D.
Neutral Evil. Evil, because he maims people, beats them to death with their limbs, tortures people, and, most importantly, believes in sterilizing people that are unfit. Reread that last sentence - he sterilizes people that he thinks are unfit. Let it sink in.
Nobody cares that he gives alms to the poor or that he has never hurt a child. He could just as well be saving babies from being eaten by dragons every other day. As long as you actively torture and sterilize people (i.e., have not stopped doing this a long time ago and repented for it), you are evil.
Neutral, because he basically only does what he thinks is right. The one point where I had difficulty with this reasoning was the "staunchly loyal to his friends" part, but that's not contradictory in any way - people of neutral alignment can feel as strongly for someone else as any other people. Lawful people will tend to always follow a code of conduct (e.g., honor an agreement even if they don't want to), whereas chaotic characters will naturally be unpredictable (e.g. stabbing their friends in the back for no discernible reason). I believe this character falls between these two extremes.
This line of thought keeps with the philosophy that a person's alignment is dictated by their actions, not their intentions. I'd be glad to argue about that too, if anyone desires to.