I BECAME A DRAGON IN THE SORCERESS'S HAND

Manga information:

I Became a Dragon in the Sorceress\'s Hand , it is a Manga/Manhwa/Manhua translated in English, written by びーびーびーといっと! 天神学園浪漫あるばむ This Comic is About
For a dignified veteran player like me, if I crossed over into my favorite game, I'd be the most powerful character, I'd be able to rewrite the ending of all my favorite characters to make them look good. However, I did cross over, but why am I just a little pet at the mercy of the sorceress? Can I still change the fate of the characters I'm trying to save?