The song M.O.B. by JR Castro is about a man who gets caught up in a toxic relationship with a woman who only wants him for his money. He realizes his mistake of trying to treat her like a long-term partner and pillow talking with a fake person. Despite his big dreams, he understands that money is more important than such fake relationships. The song reminds the listener of a story the singer's mother told him about a penny spent, signifying the importance of valuing money and being cautious about who to trust. Overall, the song is a cautionary tale about being aware of people's intentions and prioritizing one's financial stability over temporary pleasures.