Meme born out of a traffic accident involving the Japanese Niconico/Youtube streamer group S4/S4U and their friends on their trip to Hokkaido. During the incident, the entire camper van they were riding in rolled over on its side on the expressway, though miraculously they all made it out alive with only minor injuries at worst.
Because of the appearance of the group (all resembling stereotypical otakus), how jinxed that the incident happened on the first day of their trip, and the fact that the accident happened shortly after they were joking about traffic accidents (death flag ahoy!), the video instantly achieved memetic cult status on the Japanese internet and has since become memed and parodied in various media.
