Another villain could be Doctor Octopus. His mechanical arms are extremely powerful and his intelligence makes him a formidable foe. He could be after some scientific discovery that both Spider Man and Wasp are also interested in. This would lead to a battle of wits and strength as they try to outsmart and overpower him to protect the discovery.
The Vulture could be a great villain. He has his own flying capabilities and could pose a real threat to Spider Man and Wasp. His experience and his greed for valuable items could lead to some intense battles with the duo as he tries to steal some high - tech gadget that Wasp has been developing.
Mysterio would also be an interesting choice. His illusions could really mess with Spider Man and Wasp. They would have to constantly be on guard and use their combined senses and powers to see through the illusions. Mysterio could create scenarios where they seem to be in different locations or facing different threats, making it difficult for them to fight back effectively.
Annihilus would be an interesting choice. As a powerful alien warlord from the Negative Zone, he could bring an otherworldly threat. His hunger for power and destruction could force Spider Man and Nova to think outside the box. They'd have to use their combined skills and perhaps seek help from other superheroes to stop him.
A tech - savvy villain who has developed a device that can disrupt the Pym particles. This would be a huge threat to Ant Man and the Wasp as their powers rely on these particles. The villain could be a former colleague of Hank Pym who feels betrayed and wants to use his knowledge to take over the world using the chaos caused by the disruption of the Pym particles.
In a fanfiction, the lemon could be a symbol of purity or a source of energy. Spider - Man, with his sense of responsibility, would want to protect it. Wasp, with her scientific knowledge, could analyze it. They might interact with the lemon in a way that it starts to communicate with them on a psychic level. This could lead them on a quest to find out the origin of the lemon's power and along the way, they face challenges from other super - powered beings who also want to harness the lemon's power for their own gain. This would involve a lot of action, adventure and some deep conversations between Spider - Man and Wasp about the nature of the lemon and what they should do with it.
Perhaps Sabretooth could be the villain. He might be targeting Wolverine specifically, but his actions in a big city draw Spider - Man's attention. Sabretooth's savage nature and powerful claws would pose a great threat. Spider - Man and Wolverine would have to work together to defeat him, with Wolverine having the personal vendetta and Spider - Man the sense of justice for the city.
I'm not sure if there is an existing fanfiction exactly like this. It could be a very strange and unique concept. Maybe someone out there has created a story where Spider Man and Wasp are involved in a situation related to a 'birthdaysuit' in a lemon - like, out - of - the - ordinary way. But it doesn't seem like a common or mainstream fanfiction idea.
It could be Doctor Octopus. He's always been a formidable foe for Spider - Man. In this fanfiction, he might have a plan that involves not just Spider - Man but also threatens the Avengers in some way, so they have to fight him to protect Spider - Man.
The Vulture could be a great villain. He could target Mary Jane to get to Spider - Girl, thinking that Mary Jane is a weak point. His aerial attacks would pose a new challenge for Spider - Girl, especially if Mary Jane is caught in the middle.
The Green Goblin is one of the main villains. He has his own set of powers and is always causing chaos in Spider Man's city.
It's possible, but I haven't come across one. The idea seems really out - there. Maybe some really creative and boundary - pushing fanfic writer might have thought about it, but it's not a common trope in the fanfiction world that combines these elements in this way.
One common theme is teamwork. Since they are both superheroes, many fanfictions focus on how they can combine their unique abilities to achieve a common goal, like saving the city from a powerful villain.