I'm in the same boat as you! Although I don't think this is an explanation as to why I'm fixed bottom!taru I would still like to share my experience: back when I first started interating with Genshin content, bottom tartaglia was rare if not nonexistent. people would even joke about how he "didn't have an asshole" and that rubbed me the wrong way lmao
Maybe that was the trigger. I just pictured Tartaglia taking fat dick up his ass and that awakened something inside me. Whatever the case, I just LOVE seeing him stuffed. pillow princess Tartaglia? Hell yeah! bratty bottom Tartaglia? hell yeah! power bottom Tartaglia? HELL YEAH!
He's a prideful warrior who's always up for any challenge! No matter who (or what) it is, he will take them!