The universe is built upon Laws—mysterious forces that govern everything from fire and water to time and space. To humanity, they are unknowable, but to the rest of existence, they are the key to power, survival, and dominion. When Earth is abruptly integrated into the wider multiverse through the System, its people are thrust into trials that will determine their place in the grand scheme of things—or their extinction. For Kei, a laid-back 13-year-old with a love for music and no remarkable talents, this is just another curveball in a life spent lounging on the beach. Assigned the enigmatic Law of Sound, Kei must navigate deadly challenges, forge alliances, and uncover the nature of the System that has upended everything. Alongside Mia, his sharp-witted yet physically fragile friend, Kei begins a journey through trials that test not only their strength but their understanding of the very fabric of reality. As Kei struggles to adapt, he discovers that even the smallest ripple can create waves—and those waves might be enough to shake the foundations of existence.