Maybe the dark alley, big old man hands, loli looking bodied yukkuri....."the 2 alone in that dark alley".....let's just say that if that's a gold badged bodied yukkuri and that isn't her owner, we may call the cops on the suspicious guy.
That's one possibility. However, without any other evidence, nothing can be proven; good or bad. That is unless the artist gave a description that mentions danger.
there is also the whole "dark shading" enviroment, it's usually done to be omnious signals of somethiing "not nice" brewing, so there may be chances of it being danger, and if toawa actually has a continuation that proves the danger, then it may give more reason to believe it's danger worthy.
I can see why the danger tag applies, but to be honest, I'm getting more of a Big Daddy/Little Sister feel from this. I'm under the impression anon's going to beat the living shit out of anybody who wishes to do terrible things to Reimu.