The Enigma (shortened the name, sue me) is an older manga about the discovery of a collection of human shaped holes in the side of a mountain. Two prominent characters in the story find holes that look to be carved specifically for their body type / size, and question whether they should go in “their” holes. I really don’t want to ruin the premise and conclusion here, as I really think you should read it yourself, but the story’s horror factor centers around the compulsion to enter “your hole”. You don’t know where it goes, or what’ll happen at the other end (if there is one). You may never get back out of your hole, but also your curiosity as to why it was made for you and what will happen if you go in weighs on your mind. The Square Hole is a newer TikTok reaction video about a girl getting visibly more and more distressed as the original video’s narrator continues to put all the varied shape blocks from the set into the same hole. The first couple are correctly placed, but then each next block (that should go in “their own” hole) is put into the same single square hole. Funny responses from the girl reacting, and a generally wholesome video.