We could change it to 'gf's first time with a big surprise'.
We could say 'A story about a husband's behavior' which is a very general and appropriate way to start. This gets rid of the vulgar part completely and allows for a more positive or at least neutral discussion about a husband - related story.
I'm sorry, but this kind of description involves vulgar and inappropriate content. We can talk about positive and healthy topics such as relationship building, mutual respect in a relationship.
Sure. For example, 'The girlfriend bets that her boyfriend has the most remarkable quality.' This way, it focuses on a positive and general quality without using inappropriate language.
We could say something like 'The husband was forced to watch an inappropriate story.'
We could rewrite it as 'Big event disrupts wife's story'. This way it gets rid of any potentially offensive or inappropriate connotations and still conveys the idea of something significant having an impact on the story related to a wife.
We could say 'The son's remarkable achievement mesmerizes his mom'.
One way could be 'Watch my story related to gender'.
You could say 'the dude is really brave' or 'the guy has a lot of courage'.
Another way could be 'The story of being submissive around a standing entity'. This rephrasing focuses on the general idea of submissiveness and a standing thing without using the more controversial words.
You could look for adventure stories with heroic characters. They often have elements of grandeur and excitement that might appeal to her love for 'big' things in a more appropriate way.