Asa Kazuma is a carpenter and hedge trimmer who debuted in SASUKE 21 as the #4 SASUKE Trials qualifier. In the competition, he was able to make his way through most of the obstacles in the First Stage, but ended up timing out on the Soritatsu Kabe when he was unable to scale it. He participated in the SASUKE 22 Trials, but failed to qualify for SASUKE 22. He returned in SASUKE 27. There, he got his revenge on the Soritatsu Kabe and went on to complete the First Stage. In the Second Stage, however, he went out on the Double Salmon Ladder when he failed to clear his final rung.
For SASUKE 28, Asa became one of the four New Stars, along with Urushihara Yuuji, Matachi Ryo, and Kanno Hitoshi. He became only the second of five to clear the First Stage, doing so with over 16 seconds left. In the Second Stage, he had no trouble with any of the new obstacles, and reached the Passing Wall with 50 seconds, and though he struggled there, he still cleared with 25.13 seconds left. On the Third Stage, he cleared the first two obstacles with little trouble. However, his strength was sapped by the time he had got to the third ledge of the new Crazy Cliffhanger, and he slipped and fell into the water before he could attempt a swing to the final ledge.
In SASUKE 29, he blazed through the first stage and completed it with 30.30 seconds left, the fastest time of the day. Despite the significant changes to the Second Stage such as the 45 second time reduction and more powerful jets in the backstream, Asa became only the third out of the 21 who attempted it to clear the stage, doing so with a narrow window of 4.05 seconds remaining. He made it back to the Third Stage for the second time in a row. As with last time, he completed the first two obstacles. However, he failed the Crazy Cliffhanger once again by failing the transition to the final ledge.
After SASUKE 29, he flew to the USA alongside Matachi Ryo, Kanno Hitoshi, Yamamoto Shingo, and Urushihara Yuuji and represented Team Japan in the American Ninja Warrior: USA vs. Japan special. There, he ran the First Stage up against Brent Steffensen but lost the match when he failed the Giant Cycle,when he jumped so high he hit the wheel with his head and lost focus, and Brent cleared the stage. Then, he ran the Second Stage, this time up against James McGrath, but yet again, lost the match when he failed the transition of the Double Salmon Ladder and James cleared the stage. He was nicknamed the Speed Demon by NBC for his First Stage run in SASUKE 29.
In most of his competitions, he wears a Japanese Character below the word SASUKE on his back. In addition, he has a specially made pants for Sasuke reminding him of his goal. He is also one of the more emotional competitors showing emotion in defeat and victory. For these reasons, he is sometimes called, "The Spirit of Sasuke"
In SASUKE 30, he once again cleared the First Stage with the fastest time again, with 35.55 seconds still left on the clock. He also cleared the Second Stage with yet again the fastest time, 10.00 seconds still left on the clock. However, he failed the Crazy Cliffhanger for a third straight time where he once again failed the jump to the fourth ledge.
|21||45||Failed Soritatsu Kabe (First Stage)||Digest. Time Out.|
|27||55||Failed Double Salmon Ladder (Second Stage)||Last rung.|
|28||58||Failed Crazy Cliffhanger (Third Stage)||Failed to hold on and fell into the water. 3rd Ledge.|
|29||96||Failed Crazy Cliffhanger (Third Stage)||Transition from the 3rd to fourth ledge. Failed Jump.|
|30||2998||Failed Crazy Cliffhanger (Third Stage)||Transition from the 3rd to fourth ledge. Failed Jump.|