How Did Someone from Another World Come to Kivotos?

(Note 1: This is a joint article between the games "Celeste Files" and "Genshin Impact" and the novel "A Certain Magical Index". These are the author's favorite works. Please do not make malicious comparisons to start conflicts.) Abydos, a college in Kivotos, is about to close due to debt problems. For the sake of their college, the only five students left here formed a suspension countermeasures committee to pay off the college's debts. However, one day, in the desert on the edge of the college's jurisdiction, a young man named Si Ming appeared. After that, the peaceful life was completely broken, and the original story took a different path because of this boy! Academy City, the Roman Orthodox Church, Teyvat - Solstice Kingdom, countless forces with their own purposes ended up entangled together! Color, the abyss, and even higher threats have descended on Kivotos! And in this series of events, the secrets about Si Ming began to be gradually revealed... (Note 2: This article will have a lot of original plots. The first few chapters have less original plots just to lead to the following. If there are parts of the world view later that do not match the original work, it is because the original work has not reached this point when the outline was written. Everyone can just read it as a parallel universe.) (Note 3: This article will be a long-term updated work. Whether readers like it or not, I hope you can comment positively. Whether it is suggestions or criticisms, I will humbly accept them and make corrections in subsequent updates. Thank you everyone!)