It's Anubis and it's actually cool and loved project here. It's an open-source Captcha that filters out bots, and it doesn't track you around the web, unlike Google or cloudflare captcha.
I understand why people choose it, but if I see the catgirl I close the tab - same is I get the test from cloudflare.
I was startled by the girl the first time as well, but once I learned what it is, I accepted it. Like a garden gnome on someone's front yard.
Isn't it easier to just .. start loving it instead?
You may want to check upthread how loved it is :)
I, for one, don't hate it, but I hate what it represents and see its existence (rather, the reason for its existence) as a defeat for the web.