Ruvyzat is depressed, and sad. Even though he is emotionless, he now is just sadness, no happiness (like he had any before), no mad (he did have before), and yeah, he was only sad. And why, you might ask? The broken vow occured. Sarvente broke the vow that Ruvyzat would protect her forever, causing Sarvente to die. (Yes, Ruv only feels anger and sadness, but now he has no anger or mad.)