I love everything about this story. What a great premise to get them together. And Severus's spell-craftre art is amazing. Super job!
I know if it's a fic by Rakina, I'm going to love it!
I do see a slight problem in continuity. "About that: you took my advice on your genital problem?" Snape asks this just a few minutes later in the same scene after he told Harry to take care of the problem. There was never any chance for Harry to be alone to masturbate.