He has shaggy black hair and golden eyes. Usually, he wears a white v-neck shirt under a turquoise jacket, a hand-me-down from Jin, with jeans.
When in Trigger Mode, he gets an outfit resembling Yūma's C-rank uniform, but his jacket is teal with black stripes whereas Yūma's is black with white stripes, in addition to black padded gloves.
Karasuma is a laid back, friendly individual, just like Jin; he likes to tease Konami, and makes fun of her frequently. In battle, though, he becomes very serious, completely focusing on his goal. He is also quite responsible and, as stated by Jin, "He is a good teacher." He has a colder side to him and rarely seen smiling. He constantly makes up small lies to get a reaction from Konami.
(About himself) "I'm the scruffy hottie. Nice to meet you." 
(After lying) "I lied."
(To Osamu) "Those who lack the tools remain cautious. You won these two matches because you didn't get into a poorly-planned firefight and focused on manipulating the situation." 
His nickname comes from the fact that his surname, a combination of 烏 (crow), a bird species, and 丸, looks very similar to 鳥 (Bird) and 丸, which is pronounced Torimaru.
According to the Volume Extras, his jacket is a hand-me-down from Jin.