Hot Marat is an emote that players can get for 0 V-Bucks. If you look at the news on Fortnite, they credit Disney for the emote. Apparently the emote is from the new movie Wreck it Ralph 2 and Fortnite is currently collaborating with Disney. If you look at the leaked files for Fortnite, there is a file of Ralph walking by and waving and then he leaves.
This file can be seen at Risky Reels, on the projector screen. It spawning is inconsistent, so if you want to see it, try looking at the projector for a while