K5, I feel that this blurb is good but not great. It has clear sentences and makes good use of action verbs. It certainly conveys an expectation of steamy scenes. That seems to be what you were going for, and it has steam aplenty.
I don't need all those scenes listed for me. Okay, to be fair this is not a list of scenes but a list of story beats. It's a summary of the entire story, and too much like an outline for my taste.
I favor formulated blurbs. The traditional wisdom is that a book blurb, like an elevator pitch, should answer these questions: Who is the main character? What is her conflict? Why should I care?
Personally, I think that last question can be a big ask. I accept in its place an interesting hook about the setting where the story happens. This is why so many movie trailers begin with "In a world where..." Also, anything an author can do to suggest the tone is bonus.
Joan: We have a name, but I nothing about her. Is she a secretary? Accountant? Salesperson of the Year? Is she a.disgruntled housewife who re-entered the work field?
The conflict: Are the brothers fighting over her? Is she torn between loyalty and her urges? Between honor and duty?
The Why: Actually, you've this part covered.
I don't need to know about the motivation of the brothers or the fact that Joan has both a husband and a boyfriend. I do need to know who we are talking about even if its a simple descriptive phrase like "twenty-something hard-drinking lawyer Joan."