How would you describe the relationship between Sasuke and Karin?
Deep. In fact throughout the times they spent together Sasuke .
developed feelings for Karin. That became relevant when he awoke a new power to save her during their fight with キラービー (Killer Bee). When an うちは (Uchiha) learns to love changes occur with their visual powress. It increases out of hatred and love - out of the desire to save somebody. Even if they are apart now Sasuke still cares as much for Karin as for Sakura. The two have always been liked on a similiar scale by him. Karin is like the voice of the Sasuke fandom! (laughs)