Princess Bubblegum's Rock T-shirt

Princess Bubblegum's rock T-shirt is black with what seems to be two burnt/roasted marshmallows on sticks that are strangling a yellow snake in water. Marceline gave it to Princess Bubblegum as a gift. Jake mistakes it to be Marceline's when they recover their things from the Door Lord in the episode "What was Missing ," but is claimed by Princess Bubblegum who said she wears it all the time as pajamas. After retrieving the shirt from the Door Lord, Princess Bubblegum tells Marceline that the shirt means a lot to her.

Trivia

 * At the end of the episode, where Princess Bubblegum is seen running away, her shirt is colored magenta instead of black.
 * The shirt and how much it means to Princess Bubblegum causes Marceline to blush. This, along with the "I'm Just Your Problem" song contributed to the Mathematical! Controversy.
 * Marceline is seen wearing it in the "What Was Missing" promo art.
 * The shirt's design was licensed by welovefine.com to make a real-world T-shirt.