One common theme could be love and affection. Since it involves a 'beso' (kiss), the fanfic may focus on the deepening relationship between Ash and Serena.
In the comics, Eddie and Venom don't get married. Their bond is more about mutual survival and shared experiences than a marital commitment. They work together to face various challenges, but marriage isn't part of it.
Definitely not. Eddie and Venom have a complex, mutually beneficial partnership, but it's not a romantic relationship. It's based on mutual dependence for their own purposes rather than love.