Danbooru isn't that kind of site. You're thinking of DeviantArt. We don't do artistic collaborations here. We upload finished work, especially the sort that is hosted in Japanese-language-only sites or where things might be deleted, and could use the sort of soft translations we do here.
If this is your own work, note that it's HEAVILY discouraged for you to upload your own work. (Otherwise, you're missing artist and source...) If you work belongs here, someone else will likely think so, too, and upload it, themselves. If you want to upload your own work and talk about whatever background you made up for your original characters or have other people color your sketches, again, that's what DeviantArt is for.
Furthermore, you really shouldn't be just making up your own tags just for the stuff you are uploading. Tagging guide. You should also pay attention to the difference between character tags and other kinds of tags. (Although it's pretty moot, since there's no chance this passes the mod queue.)