Welcome!

Overall, I liked this a lot. Very solid first entry. I hope to see this level of quality in all of your future comics. As was already mentioned, these can be sized down considerably, I had to shrink them a lot to read and view them properly. But it sounds like you already have a handle on that, so it's all good. Another thing I would say to work on is the lettering. Your lettering isn't BAD by any means, but could use some improvements to make it flow better and be easier to read. My first suggestion would be to keep the font at a consistent size. I noticed that in some places it was made smaller due to not having room for the scripted lines in that panel. In cases like these, a few things can be done. I'd recommend either breaking up the lines into multiple balloons so that you can fit it more easily around the character, or even consider editing the script to still say the same basic thing, but with less dialogue so that it doesn't appear crammed in there, and can remain at the same size as all other text. I think the only time text should be noticeably changing size is if the character is whispering or yelling. Another thing is to watch your alignment. Usually, you want to align to center, and place the words so that they fit the shape of the bubble as closely as possible. I saw in some places the text was aligned left, so had a flat edge inside a round balloon, which looks strange.

One other thing that could maybe help for the future is working on drawing the characters at different angles. Up until the very end, pretty much every character is shown from straight on. Adding some new poses and angles will do wonders for the dynamics of your work, and make these even stronger, very formidable. I know this story took place primarily in a small train car, but there is still a lot that can be done in small spaces to make them more dynamic and interesting.

I really like the colors, I think they work very well.

So sorry for the above rant, though. Just a few small things you can do to make these that much better. Again though, very strong intro. I would love to see you go up against JBA1987 and the Squad... Just saying. I feel like a train NEEDS to be involved, haha!

I will downsize the intro pages so they are easier to read thanks for letting me know that one!

Yeah, the format you're working is way too large for web presentation. By all means work large, especially if you're ever looking to print your solo stories or something, but screen sized panels eat into the flow of your story when the audience has to keep scrolling. Beyond that, it's a LOT of straight on angles, which gets a little tedious. Even when you try to draw something in perspective to vary up the angle, like the first panel of the second page. The figure's still standing facing front. Probably because it seems like the background's just drawn diagonally to give the illusion of perspective but following any logical angle. And then there's the anatomy of the leg in the bottom panel of page 3. The proportions & foreshortening are really off putting. Practicing figure drawing & introducing more variance into your body shapes might be helpful. This is a great place to get that practice so be sure to put it to work here.

MORE PRETTY THIEF GIRLS YES you should fight Animal Girls XD (you got that, jba??)
like jba said though the page size is HUGE, honestly Im a bit surprised the mods didnt ask for a resubmit (not that they dont work hard and we love them for it). its hard to get a real good flow of the story this way. but! I think your character is cute and I cant wait to see her battle!

My only advice right now, because this is a p strong intro comic, is that you need to size your pages down! That will help with the other things: the inking and the lettering feel very thin/small. Working at a large filesize is more helpful when you aren't able to make a straight line (ahem, like I can't), and when you need a particular level of detail.
Once I zoomed out, though, I liked this a lot! Great progression and good use of the page constraints! Can't wait for more!
Past that, I feel like based on the character and her traits, it's very important that I call dibs on first challenge, vs the Squad...