These are one of my favorites and they aren't all that rare. They are the main antagonist and usually the most deadly character.... And they fall in love with the Main protagonist. You're probably asking, do they have bad back stories too? The ones I've seen do! In fact... I wouldn't see anything wrong with the Yanderes, Yangires, and Mayaderes being sisters or brothers.
Examples: Esdeath from Akame Ga kill, and Illya from The Fate/Stay Night.
You would be surpised how much they are actually used, they are used more than Yanderes but people just didn't know about them.