Thanks for finding the source. My Pixiv-fu wasn't sufficient.

HaxtonFale said:

Thanks for finding the source. My Pixiv-fu wasn't sufficient.

Use http://saucenao.com/, a reverse image search specializing in finding sources for Pixiv and similar sites.

I didn't even notice they had done a costume switch until I saw it in the tags. Those grins were chilling enough to deflect my attention away from the costume switch.

DevonM said:

I didn't even notice they had done a costume switch until I saw it in the tags. Those grins were chilling enough to deflect my attention away from the costume switch.