It basically refers to a small penis in Korea. When Jimin was talking about his parent's dream, his parents had mentioned seeing a small chilly pepper hanging from a tree.
When you simply take an ice rod and insert it analy into the girl. After the butthole is numb you cut the edges of the butthole so it is bleeding. When you insert your penis into the butthole you will come out with ketchup on a hotdog, the blood makes the feeling more slick.