Lisa urges Bart to keep quiet about their involvement in Martin's death, similar to Lady Macbeth convincing Macbeth to calm down and lie about Duncan's murder.(also Like every other accomplice in the history of the world)
Lisa also states that she has a dark side, like Lady Macbeth.
After Bart steals Sideshow Mel's bone, we see his true long hair.
Some of the Nicknames of Martin at his Funeral are: Martin Prince, Martin Princess, Martin Priss, Fartin' Priss, and Martin the Brown Nosed Reindeer. The last one references Rudolph the Red-Nosed Reindeer and the term "Brown nosed."
According to Nelson, Martin apparently has a fear of heights.
When Nelson hears Bart and Lisa confess to Martin's apparent death, Lisa tries to get him romantically interested in her again. The two dated in "Lisa's Date with Density."