If you haven't seen Game of Thrones Season 7 Episode 1, and you don't want any surprises spoiled, do NOT keep reading.
Then again, this isn't exactly a plot spoiler, so it won't really ruin the show for you. Although for some fans this moment was extremely unwelcome.
Last night Ed Sheeran made a cameo appearance on HBO's Game of Thrones. He didn't fight any battles and he didn't have any important dialogue, he just sat near a fire and sang a song.
Some people are making a big deal out of the fact that Ed Sheeran somehow "ruined the realism of the show" but those people need to realize that there are a ton of more recognizable faces on the show. So perhaps they should chill out a little.