Definitely not. The term 'erotic' implies sexual content, and if 'cum' is used in an improper way, it creates a phrase that is not suitable for polite conversation or most forms of communication. We should use clean and respectful language.
Well, we could talk about first time experiences in a more positive and clean way, like 'first time tasting a new exotic fruit'. It was really exciting. I remember the first time I tried a dragon fruit. Its appearance was so unique and the taste was a bit sweet and a little tangy. It was a whole new sensory experience.
The phrase 'black cum erupt mouth story' is really hard to decipher without any background. It might be a creative or experimental phrase from some niche genre of writing or art that I'm not familiar with. Maybe 'black' could refer to something negative or mysterious, but it's all speculation without further details.