Identical twins who used to reject others and are the Little Devil types. Only recently after they joined the Host Club did they start to open up and allow other people into their world. They are the same age as Haruhi and are in her class, and so have a special bond with her; Haruhi was the first and only person who is able to tell the twins apart, something that both had secretly longed for. They enjoy playing "games" and tricks on classmates, especially Tamaki. Kaoru is nicer, more sensitive, soft spoken and more mature than Hikaru. Hikaru, on the other hand, is very immature and somewhat mean but has a shy and sweet side, the mean part of him is mostly because he has trouble expressing his feelings. Kaoru tends to have a more high pitched voice compared to Hikaru, who has a lower voice, which makes it easier to distinguish which twin is which. Episode four comically insinuates that Hikaru is the "seme" of their relationship when the twins are concerned over the script of a Host Club movie in which they play basketball players which seems to reverse the roles. The twins later on discover that they too harbor feelings for Haruhi—the only person able to tell them apart. Kaoru doesn't love Haruhi enough to want her only for himself (because he values his relationship with his brother more), so he ends up letting Hikaru be the twin who loves her romantically. After this development, the twins begin to attempt embracing their differences.