Spidermandy (The Grim Adventures of Billy & Mandy)

"Spidermandy" is the first half of the twelfth episode in the fifth season of The Grim Adventures of Billy & Mandy.

Plot
When Billy finds his "son" Jeff the Spider lying in his bed with "Spider Pox", he goes to Mandy for help to get rid of the giant spider. While ignoring Billy, the next morning Mandy awakens afflicted by Spider Pox too, developing four additional arms and the ability to produce spider web. Mandy's condition progresses and she completely turns into a giant spider, who captures Billy's parents and Grim.

Why It's Venomous

 * 1) Plot holes:
 * 2) * It was never explained how Jeff the Spider got the Spider Pox, along with how Billy got a clamp on his head.
 * 3) * How could Mandy get the Spider Pox, anyway if Billy never brought over Jeff?
 * 4) Jeff sleeps on Billy's bed due to the Spider Pox, Harold shouts at him to get out of his bed and Milkshakes scratches him when trying to sleep on the television. Then, he gets kicked out of Mandy's when telling her that he couldn't sleep on his bed and gets chased by Mandy in spider form.
 * 5) Billy doesn't even bother to take care of Jeff the Spider's illness and instead tries to find another way to sleep to the point of waking up Mandy for help at 3:00am when finding out that Mandy is Jeff's mother.
 * 6) Mandy basically kicks Billy out of her house when Billy tells her to be Jeff's mother to take care of the Spider Pox, but then again, it was 3:00am at the time. Then, when becoming a spider, she traps Billy's parents and Grim in the web for no reason at all.
 * 7) Mandy's spider design looks extremely messed up and disgusting, along with everyone in Endsville's designs at the end.
 * 8) Lots of gross-out humor here, such as Billy's teeth and eyes popping out, the mold on the sandwich and milk Grim takes out, the spit close-ups on both Jeff the Spider and Mandy's spider design, Billy using Jeff's fangs to fill up a potion to cure Mandy's spider form and even him burping when drinking lemonade at the end.
 * 9) Bad ending: When Billy drinks the lemonade used to cure Mandy's spider form, he lies in bed, asks Grim about the Spider Pox and when opening the door, he finds everyone in Endsville having the Spider Pox, which just looks even more messed up and disgusting and scares Billy.

The Only Redeeming Quality

 * 1) At least the drink Billy gets from Jeff's fangs helped cure Mandy's Spider Pox, but even that doesn't excuse the bad ending.

Trivia

 * The episode title is a reference to Marvel's Spiderman.