Pixiv subtags

There are quite a lot of titles like pixiv_rengai that have very few posts. Maybe we should make them imply the general pixiv tag?

Yeah, I've just read pixiv wiki. Why would we use it only for images that refer to pixiv itself?

Why would we use it for anything else? This is how the deviantart and niconico tags work as well.

Well, try *pixiv* copyright search in the tag list. There are lots of those titles. If someone is willing to find more pixiv pojects, how is he supposed to do that? And the pixiv tags seems quite obvious choice to me. Well if not, then maybe we should introduce another tag to get those titles together?

I guess if there is a real tangible need to group them pixiv project could work but they have nothing to do with each other aside from source site.

Yeah, that's pretty much what I wanted. Maybe there will be more opinions on this one.

A tag group wiki page could work, but then again not many people notice those exist.