My Senior Sister Knows How to Use Magic

This is a world where science and magic coexist. Here, some pursue powerful magic, while others seek eternal truths. A science prodigy who crossed over from another world starts as a humble librarian, wielding magic in one hand and truth in the other, kicking open the door to a new era. Some call him the pioneer of magic, others say he is the founder of science. And there are those who describe him this way. In the new era, Blair is the embodiment of evil.