On his first day of transferring to a new high school, a loner named Mori Buntarou, is cajoled by a classmate into climbing the school building. Despite knowing that one misstep could send him spiraling to his death, he moves forward, and upon finally reaching the top, Mori experiences a sense of fulfillment. That feeling, which seems to be telling him, "You're alive!" gives birth to an adrenaline for rock-climbing.
The Climber is a completed manga by Sakamoto Shinichi, first published in 2007. It blends psychological, romance, sports and philosophical. You can read all 170 available chapters of The Climber online for free on MangaPulse; the newest is Chapter 170, added 2024-12-30. The series is finished, so you can read it from start to end in one go.