I have a theory about this!!! I also searched up the symbolism of a white horse and saw that it can represent death in Christianity so I wanted to look more into it (mind you this theory comes from a quick Google search)
Thread: https://twitter.com/soobacado/status/1351551126173204480

From what I found, a white horse can be found in the Book of Revelation as one of the horses that the four horsemen of the apocalypse are riding. Notably, the white horse is the first of the horsemen. Considering the Chaos Chapter is coming, I'd say this is apocalypse symbolism

But it's just a horse, where is the horseman? Well I think the horse is circling Yeonjun in order to make him the rider and become the first horseman of the apocalypse. I think this makes a lot of sense considering Yeonjun sees himself as a monster in the +U

Maybe he becomes a horseman against his will but either way, the chaos of the +U starts with Yeonjun especially considering the MMA 2019 performance. Chaos descended after YJ was taken by that devil so I can see him being a horseman of their impending apocalypse

I also think YJ is the white horse's rider because the Book of Revelation specifically describes the first horseman wearing a Crown and I think we all know the connection between YJ's horns and a crown

Furthermore, the first horseman is often seen to represent Christ or the antichrist which fits with YJ. I have a theory the YJ already died and was brought back to life by the cat so the idea of resurrection and also YJ thinking hes a monster lines up with Christ and antichist

And that's it! I really think this ominous scene has a few ties to the Book of Revelation and YJ possibly becoming the first horseman of the apocalypse that is to come in the Chaos Chapter. If you read this all I hope you enjoyed!
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