Monty and Vanessa have a 'Romeo and Juliet' type relationship. They fell in love despite their fathers being sworn enemies.
The relationship between Vanessa Doofenshmirtz and Monty Monogram was first introduced in the episode "Minor Monogram ", which was also the first episode that Monty appeared in.
In "Minor Monogram ", an angry Vanessa breaks up with her boyfriend, Johnny, when he acts like a video game is more important to him than she is.
At the end of the episode, Vanessa says, "I think it's time I tried a... good guy." to Rodrigo as Monty smiles at her before flying off the building.They meet for the second time in "Sipping with the Enemy " when they see each other at Steam Noir. Vanessa starts the conversation and it seems like she has developed a crush on Monty. When they both order a "cappuccino with chocolate powder and a ginger scone", he offers that they drink them together.