You can try looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of various fanfictions, and there's a good chance you'll find some Spike x Jerry ones there.
One good Spike x Jerry fanfiction could be a story where they team up to solve a mystery in their shared neighborhood. Maybe they have to find out who is stealing all the cheese in the area.
In fanfiction, if Tom kisses Spike, it could be a really strange and comical situation. Spike might be extremely shocked and confused at first. He could react by growling or even chasing Tom more vigorously than usual. It would be a complete departure from their normal relationship dynamics, which is mainly based on Tom's attempts to catch Jerry and Spike's occasional interference to protect Jerry.
A fanfiction story could start with Tom kissing Spike if there was some sort of miscommunication or magic involved. For example, a magic spell gone wrong that makes Tom think Spike is Jerry. So, without realizing, he gives Spike a big kiss.
The 'x' in 'sleepy gary x jerry fanfiction' usually implies a relationship, which could be friendship, or something more complex in the context of the fanfic. It might also play with the personalities of the two characters. Gary's sleepy nature could contrast with Jerry's more energetic or mischievous personality, creating an engaging dynamic in the story.
Overcoming differences is also a big theme. Since Tom is a cat and Jerry is a mouse, their natural instincts are to be at odds. But in fanfiction, they learn to work past those differences. For instance, in a story where they have to solve a mystery, they realize that their different perspectives are actually useful in finding the solution.
One common theme is the exploration of their complex relationship. Given their history of rivalry and shared vampiric nature, many fanfictions dig deep into how they interact with and feel about each other.
Another theme is loyalty. Despite their differences and occasional rivalries, they are often shown to be loyal to each other in fanfictions. For example, in many stories, they will go to great lengths to protect one another.
Writing sexual fanfiction involving characters is generally not appropriate. It often goes against the ethical and moral boundaries, especially when it involves non - consensual or inappropriate interpretations of characters. Fanfiction should focus more on positive aspects such as character development, alternative storylines that are within the realm of good taste.
Good Spike x reader fanfiction often has a strong sense of character. Spike's personality, his brooding nature and loyalty, are well - captured. It also has a believable relationship development between Spike and the reader.