"Just take the dissection tray and use its wax foundation to cradle my broken heart, Vanessa!"
Johnny is Vanessa Doofenshmirtz's ex-boyfriend.
Vanessa's father Heinz Doofenshmirtz calls him a nice fellow and has invited him over to Vanessa's 16th birthday party. Upon arriving with Vanessa's other friends, Johnny told Vanessa that her dad did a good job with this party, and Vanessa thanks her father for getting one right for her. ("Dude, We're Getting the Band Back Together"). He later joins Vanessa at a DJ party in a junkyard, where he sees her father doing an impressive beat on the DJ box, complimenting this to be very cool. ("Brain Drain"). Johnny later joins Vanessa in her camping trip. ("Skiddley Whiffers")
However, the relationship didn't last so well as Johnny proves to be really sensitive and obsessive in nature. This was shown when Vanessa was calling him over the phone, as he once declared that a video game is more important than her. Outraged by this, an upset Vanessa finally breaks up with Johnny before hanging up and mopes over the failure of their relationship to her father, who cheers her up by saying that she should stop going for the bad boy types. ("Minor Monogram") Ever since then, Johnny had become depressed, moping over the loss of his relationship with Vanessa, especially in school, much to Vanessa's annoyance. During one day at school, Johnny was accidentally transformed into a mutant thanks to a certain DNA mix-up with a mutated hair sample, much to the class' shock. Fortunately for him, Doofenshmirtz (who has become the class' new teacher) manages to formulate a proper antidote to turn Johnny back to normal, much to the class' relief. ("Doof 101")
Johnny has an emo personality, he tends to act like a normal teenager. In "Minor Monogram" and "Doof 101" it was revealed that he is very sensitive and obsessive.
Vanessa had a crush on Johnny. Later, it is revealed that Johnny is Vanessa’s boyfriend. (It was implied while she was partying with her friends at a dump.) (“Dude, We're Getting the Band Back Together”, “Brain Drain”). In “Minor Monogram”, Vanessa broke up with him because she thought Johnny felt that a video game was more important than her. He felt heartbroken when she dumped him and he tried to kidnap her ("Doof 101").
- His name and connection to Vanessa are possibly in reference to Johnny Depp and Vanessa Paradis.
- He is typically seen with his hair covering one of his eyes.
- Johnny is a Punk, while Vanessa is a Goth.
- His initial relationship to Vanessa appears to be similar to Candace Flynn's relationship with Jeremy Johnson (in Vanessa's address book, she drew little hearts around his name.)
- He knows how to play guitar ("Skiddley Whiffers").
- He's allergic to bee stings ("Skiddley Whiffers").
- "Dude, We're Getting the Band Back Together" (First appearance)
- "Brain Drain"
- "Candace Gets Busted" (Cameo)
- "Skiddley Whiffers"
- "Doof 101"
- Phineas and Ferb The Movie: Candace Against the Universe (Non-speaking cameo)