Despite being possibly the grouchiest troll on the whole planet, Karkat relates well to people, possibly because he is mentally stable, by troll standards, and believes that showing many kinds of pity is the best way to have the capacity to hate. He usually stops insulting and whining whenever the other troll mentions he or she has some kind of significant problem that isn't worth making fun of. He is the go-to guy for several of the trolls with romance issues, like Tavros and Eridan, and even unwittingly advises Vriska, as well as Kanaya. Ironically, Karkat admits that he has problems with relationships, particularly blackrom, and thinks he sets his standards too high. His inclinations towards redrom are strictly private.
Karkat is a crab in more ways than one. He constantly insults others in the style of a stereotypical internet troll, supporting his arguments with what seems to be empty logic. Jade has even gone to the point of flipping out at Karkat. In keeping with the crab appleasshole theme of his personality, he rarely smiles. He is also often seen screaming, pounding his fists against his keyboard, or generally raging when talking to anyone. He is not particularly patient when explaining himself, making even his most sound advice appear to be random insults. He also becomes visibly aggravated when other people are having fun. ♋♋♋