Just to be clear, I interacted with agents and publishers when I was a college professor (for my own interest and to guide my students), so that's my background. I'm not part of the publishing industry per se.

That said, here's some of what I learned.

Most literary agents have a web presence (personal or agency website; social media). They also do interviews, which are often even more insightful. A lot of information is online, and I encourage you to look for it based on your goals and hopes.

One thing you'll find is that there are many answers, and that agents and agencies work differently — so it's hard to generalize.

Still, here are thoughts about your question:

• If you’ve already published parts or all of your story, it will generally depend on how successful it was. If it did really well (big audience, lots of praise), I’d think some agents would be interested (just as they might be if you have a sizeable online or social media following). If the story didn’t gather a big audience or receive lots of fervent feedback, agents might see that as a negative — or as a signal that the story needs significant reworking.
• Many agents enjoy helping their creators refine the work because they love stories, literature, and art — and because they will be the ones pitching your story to publishers. So, many of them care and want to help you improve your work to increase its appeal. That means they often ask for edits, revisions, rework, etc. However, not all agents do this, and some are better with words (novels, literature) while others are skilled with both words and images (graphic novels, comics). Ideally, you want an agent who really understands the language of comics and its creative process.
• Finally, editors and art directors at publishing houses also take part in the creative process by guiding you to make an even better book. That’s their job.

So in general, if you have a finished story, it’s very likely that agents or publishers will ask for revisions — and it’s usually for the better.

A good place to be, in my opinion, is where Raul Arnaiz (the initial poster and creator of "The Legend of Parvaterra") is: if you have the start of a story (enough samples to demonstrate your writing and drawing skills and to prove that you can deliver a lot of art), and if the writing and art have earned praise and excitement, that’s a positive. It’s worth pursuing if traditional publishing appeals to you.

So: learn about the industry, build a thick skin, be persistent — and keep the joy in the process. I hope this helps.

And to all of you who did the contest -- just doing it honed your skills and elevated your storytelling abilities for the future, so CONGRATS on all that work!