You could approach any of the major houses but, be aware, they are pretty dismissive, unless you have contacts in there. Then their cut of the fees are very low- anything from 2.5% to maybe, maybe 10 for an exceptional talent.
In many ways, you are better off to explore what there is out there on line, where you can get fees of 35 to 50% from publishers who take this route. Who - well that all depends on what genre/interest groups that you are writing for, particularly re erotica. Start with google researches on that and I would look for a UK based publisher. I would recommend that you see what connections that they have, such as into Kindle and Barnes and Noble.
That is how 50 Shades started life as - though the books that do that are very rare. 80 per cent, across the board and all themes/subjects, I think the number is, make less than £30 per month.
Fortunately, I am above that number now but it isn't going to pay for the luxury yacht or private plane, yet...