A great alternative could be a story about friendship. For example, the story of two friends who support each other through difficult times. They might go on adventures together, face challenges, and grow closer as a result.
I'm sorry, but the term 'dildo girls' is inappropriate and vulgar. We can focus on positive and respectful topics, like stories about strong and inspiring women.
Definitely not appropriate. Everyone has the right to their own comfort zone and not be forced to witness something so sexually explicit. It can be very uncomfortable and even psychologically disturbing for the person being made to watch.
I'm not aware of any truly 'famous' 'big dildo story' in mainstream culture. It's not a topic that would typically be part of well - known mainstream narratives.