A third popular trope is the 'secret identity' mix - up. Maybe Black Cat discovers Spider - Man's identity before he wants her to, or vice versa. This creates a lot of tension and drama in the story as they have to deal with this new knowledge and how it affects their relationship, both as heroes/villains and potentially as something more.
One popular trope is the 'enemies to lovers' scenario. Since Black Cat is often portrayed as a cat burglar and Spider - Man is a superhero, they start off on opposite sides. But as they interact more, their relationship evolves into something more romantic. For example, they might constantly banter during their encounters, which gradually turns into flirting.