When you pull out while having sex and "spray" sperm all over your girls face, chest, belly or ass. As it hits any of those surfaces gravity soon affects the jizz and in starts to roll "down".

A phrase to describe someone who is cognitively degenerating. Synonym of "going off the deep end". Can have varying degrees of severity.

Reference to the song "Hey You" by Pink Floyd. The line "and the worms ate into his brain" makes no sense in an otherwise linear and literal narration throughout the lyrics.