Using loli.net address redirects to SM.MS
I have not tried to search for loli.net somewhere. This address appears only if you upload a picture to the SM.MS service.
As Imgur is unavailable in China, they use SM.MS, a Chinese image hosting service. loli.net domain is just their CDN.
I'm not sure how to search for an image url through ninjastic.space and whether it's possible at all, but you can get some results using google:
https://www.google.com/search?q=site%3Abitcointalk.org+i.loli.net