Ugh, I can't believe I fucking fell for this shit.
I was a bit suspicious since in normal gacha using tickets, I always kept getting the same kinds of SR cards, mostly Zenobias, Lyras and Salamndra dupes. Now I am certain that the devs tweak the rates on a per character basis.

It makes total sense, since even games like Granblue was called out for tweaking their rates for only specific characters to drop.

That's the last time I spend money on an inferior niche Nutaku game.