The twins are both considered the mischievous, tricky, "little devil" types to attract customers. However, they do have their differences. Kaoru is nicer, more mature, and considerate to the thoughts of others, while Hikaru is more childish and immature, although Hikaru is the older twin. Kaoru also chooses not to pursue his feelings for Haruhi, so that Hikaru can realize his own feelings first. The personality differences are only shown when they are separated, and there is a slight difference in the way they speak. There are several ways as to how to tell the twins apart, the most used being that Hikaru's hair parting is on the right and Kaoru's hair parting is on the left. Also Hikaru's hair color is more of an ash black color. He dyed his hair after the fight between him and Kaoru. They live with their mother, Yuzuha, a fashion designer, and their considerably meeker father, a computer software designer. Both have a crush on Haruhi, but in the end Kaoru realizes that his brother is more important to him, so he gives up on Haruhi. As Tamaki has recently realized his feelings for Haruhi, Hikaru is determined "not to lose" in winning over her heart. However, as time goes by, it seems Hikaru is becoming more and more conscious of how his suspicion about Haruhi's feelings might be true. Especially in chapter 71, when he goes to get her only to find her alone in the Music Room with Tamaki, patting his head while he's sleeping. From here on he seems to have realized the fact that his chances are slim to none. In chapter 78 he finally gets it confirmed as he once again asks her out about her feelings, in which she this time admits that she's in love with Tamaki. Hikaru tells for her to confess, and after having figured during chapter 81 that she most likely have, he gets on the verge to cry for a moment before the other Host Club members gathers around to comfort him. Though later on in the chapter, it is hard to tell whether or not the twins, including Hikaru, even had a crush on Haruhi in the first place because at one point, the twins noticed that Haruhi and Tamaki were not at all acting as to how a new couple should which gives the twins a bad feeling, so they confront Haruhi about it. She calmly replies to them how she is okay with that and Tamaki's schedule makes him pretty busy anyway, leaving them both in utter shock. Ending the scene with Hikaru and Kaoru huddled together wondering if their efforts for their scheme of coupling Tamaki and Haruhi together so they could tease and fluster them had failed. Which does end up becoming the motivation the twins needed into eagerly trying to help Tamaki plan out the perfect first date for Haruhi and him.