Only I Have an EX-Grade Summon

A brief description of the manhwa Only I Have an EX-Grade Summon: After being in a coma for three years due to a traffic accident, I woke up to find that the world of a certain game had become reality. In a world where systems and summons are the norm, people say that in order to climb the “Tower of Trials,” they must find “God Ji-nu.” But… God Ji-nu? Summons have ranks. From the lowest F-Rank to the highest S-Rank. But something is strange. “Why is my summon EX-Rank?”