Kabe Don!

Kaishin Ohno was never the flashy, outdoorsy type. In fact, he was so invisible in middle school that he was nicknamed ‘Stealth’. On the very first day of high school, however, Fate decides to drop him, literally, into the life of bouldering prodigy, Toki Natsume. After spending his youth avoiding all the obstacles that have stood in his way, the irrepressible Toki is going to show Kaishin that there is no wall he cannot overcome, especially the one that will change his life forever!

(Source: Shogakukan Asia)