Sovereign Conjurer: Ultimate Gacha in a Mix Anime World

Transmigrating into the body of the deceased Futarou Uesugi, being chosen to experience the ultimate gacha experience in a world with a premise similar with Solo Leveling, what's this? There are random anime characters that appear, some with the same back story, and some with completely different ones. But what could they be? Come read and find out *winky face* ... Enjoy, I'm testing out how to write a system Fic since I haven't created one, so sorry if it appears messy. Ps. If I mess something up with the system please let me know so I can fix it