Galaxy is an Epic Fortnite Outfit from the Galaxy set.
Galaxy is one of the more unique skins I've seen added to the game of Fortnite. It depicts a male that has been apparently consumed by the universe as he is displaying galaxies, stars, and planets all over his body. He also has what appears to be small orbs of light orbiting around his head. While most Epic skins come with a Back Bling, we have not seen one for this skin.
How-to Get the Galaxy Skin
It looks like you will have to have a Samsung device to get this skin. Here's an excerpt from Fortnite's official Android FAQ:
Play Fortnite on a Samsung Note 9 or Galaxy Tab S4 and you get access to the Galaxy outfit. The Galaxy outfit will appear as a free item for you to claim in the in-game Fortnite store. (Source)
Back Bling, Glider, and Harvesting Tool
More items for this set were leaked in October, and it turns out if you are the lucky owner of this skin then you will be receiving these additional items on November 1st!
Starting Thursday, November 1, owners of the Galaxy Note9 and Galaxy Tab S4 can exclusively access the new Galaxy accessory kit for Fortnite, which includes back bling, a glider and a harvesting tool. The Galaxy accessory kit joins the Galaxy skin as exclusive, coveted in-game Fortnite content, available as a benefit for owners of Samsung Galaxy Note9 and Galaxy Tab S4.