Kou

In the manga, his motto before battling usually includes "the three D's, dapper, debonair, and dollars." which Hit normally mishears.
In the manga, before he introduces himself, he is seen three times, spying on Maika... SPYING.

Kou is usually seen as arrogant and preppy. However, when Hit insults Kou, Kou becomes angry and tries to attack him. He is also gets upset when Hit hangs out with Maika.

instead of being cold and calculative like most rich kids, he just TRIES to look like that but due to his arrogance, snubness and a annoying self in general, and he can't bring himself NOT TO be AT LEAST SLIGHTLY empathetic... he's quite selective. he doesn't like hanging out with other rich kids because they're way too annoying, he's... REALLY selective. he likes other brag, but he'll brag SPECIFICALLY to either impress Maika OR to annoy Hit (Hit ends up annoying Kou instead due to Kou's easily irritated self).

Kou is a male Inkling with the "Mush-Cut" hairstyle. His outfit consists of Tinted Shades (The Tinted Shades are a pair of sunglasses with black frames. The rims are somewhat round and have tiny metal studs towards the hinges. The sides and lenses change color to match that of the wearer's ink. On the left side is the Inkling text from the Zekko logo in white. The Tinted Shades are completely mirrored and opaque from the outside. When viewed from behind, the glasses will appear to have no lenses), a Shirt & Tie (The Shirt & Tie is a white button-down long-sleeved shirt with a red-and-blue-striped tie. On the middle of the tie, a squid-like logo clip is seen) , and School Shoes. He has used a variety of weapons throughout the manga series but is most frequently depicted using the Undercover Brella. (The Undercover Brella looks like an ordinary black umbrella. The brown handle appears to be made of whangee, and the main shaft changes color to match the user's ink. The shield is black and semi-transparent with black beads at the end of the ribs and a brown-and-gold muzzle on top.) his eye color is black and his ink color (aka hair/tentacles and ink in general) are yellow.