Aven Astraeus is a fifteen-year-old homeless orphan in the Clover Kingdom who has spent his entire life being ignored and looked down upon. During the Grimoire Acceptance Ceremony at the Grimoire Tower, he appears to be rejected—until an impossible black grimoire with no clover descends from the sky. At that moment, his eyes transform into swirling galaxies, granting him extraordinary perception and the power to manipulate cosmic magic. Aven's grimoire is unlike any other. It can store the essence of other grimoires and perfectly imitate any spell or skill he witnesses, giving him limitless potential. With abilities that control stars, gravity, and space itself, he rises from an abandoned street boy to a feared and admired prodigy. As Aven joins the Magic Knights, he forms bonds with figures like Asta, Yuno, and Yami Sukehiro, while attracting the attention of powerful enemies and the Julius Novachrono. The story follows his journey from loneliness and rejection to becoming one of the most powerful mages in history. At its core, the novel is about a boy who was thrown away by the world, only to discover that he carries the power of the cosmos and the potential to surpass every known limit.