Moma sets off on a journey in search of her friend, who she believes is in the million-floors-deep underground world of Million Depth. However, what awaits is a constantly changing world. The true story behind Million Depth differs between timelines, and Moma's fate too changes with the world around her. Moma's past decisions have consequences that ripple into the future and even other timelines in unimaginable ways. She will have to piece together fragmented clues from her journey to solve the many mysteries she comes across. ...