Freddy Addison is a one time character who appears once in the Sabrina the Animated Series episode Witchery Science Theatre
Freddy is a character from the 1950's sci-fi movie "I was a Teenage Lobster Zombie from Outer Space" who was in love with Peggy Sue, a popular girl in school and wanted her to be his girl (Despite her father never wanting his daughter to date a nerd) while getting ready for his date at make out point, he realize that no matter what he do, he could never look good enough to be her guy.
So Freddy went to the local mad scientist's house who created a potion to make him look like a teen heartthrob, followed by entering the transformation machine. However badly time hit when The Scientist pet lobster entered the machine and fused with Freddy, making into a Human/Lobster hybrid. When he went to visit Peggy Sue at Make out point, his appearance frighten her and the other, thinking his a monster.
Somehow he found a spaceship and used it to travel around town. After meeting with Sabrina, Harvey and Chloe they discovered the truth about Freddy and decided to help him get Peggy Sue and find a way to change it back.
At the Drive-In after Sabrina revealed to Peggy what happened to Freddy, she took her to see him. Unfortunately her father along with part of the town form and angry mob and plan to destroy Freddy with a large amount of butter. Luckily the mad scientist arrived and invented a giant Nutcracker which he used turn Freddy back to his normal self and he is reunited with Peggy Sue.