Tear Jerker / Enantiodromia

• Karkat's ultimate fate. His witch, Karkinos, is said to be eternally looking for (feelings of, at least) companionship. However, it's obvious he will never get it, because he killed his companions. But as a witch, he has probably forgotten that, rendering it useless.
• Nepeta. How would that feel, knowing you're already going to become a witch on long term, and later being revealed you're going to die. Karkat killing her feels now like a Mercy Kill.