Throw in some sissification play and abdl play and I'd say you have a real winner. I would also edit out the type of school the MC is in since it doesn't match up well with him being "18" and all.
As an example, just say "School" and leave out other details related to the type of school. Just a thought. I know how it can be when writing and you are wondering about one thing while typing another thing and then what you were wondering about is what you ended up typing without even thinking, ya know?
Anyways. Good luck with this.
Thank you very much for the advice, Stranded In The Sea was my first project with which I started in 2019, so it has several aspects to improve and many details to polish and things that I overlooked, especially in the narrative, an aspect in which I want to continue improving so your comment is very valuable.