Did you ever see a poster mocked up by a fan that was so good it could be the real thing? This is not one of those times. And yet ...
Fans have some serious skill. Oftentimes they'll put together images, songs, films and costumes that put the pros to shame. Other times they just go for some silly fun. Such was the case with one fan who took images from Thor: The Dark World and made it look like Thor and his brother, Loki, were uh ... well? Let's just say that they seem to be very happy to be in each other's company.
Now while there's certainly nothing wrong with that (minus the incest), it's obviously not real. Well, to most people, anyway. Unfortunately, it seems like one theater in China didn't get the memo and posted these images as though they were official marketing material.
Not only was a full-sized cardboard standee created, but it was also obviously manipulated by someone at the theater proper. Which means someone there is either incredibly naive or attempting a really strange joke on the Chinese viewing public. Or maybe the poster maker is just suffering from a case of wishful thinking.
In any event, for better or worse, "Loki and Thor love each other very, very much" isn't the plot of The Dark World. At least, so far as we know.