Hello! I am going to base this critique solely on the drawing itself, rather than the character as you've described her in the description. first and foremost, I think that she is an interesting character! I like her design, and her body is very sexy. we don't often see such full-figured OCs, and I like that you took that into account when creating someone unique.
There are a couple of ways that you could strengthen this piece, and I hope that I'm able to give you ample advice in order to do so. the first thing I would recommend is to study anatomy rigorously. your proportions aren't too terribly off, but some of the little mistakes draw attention to themselves and hence weaken the drawing. If we look at the hip area where they flare out from the waist, we see that it is asymmetrical, and a little unnatural. As well, the shape of the legs is off and the structure of the feet does not look realistic. A good way to fix this is to study anatomy, as I said before. I would like to challenge you to sit down for at least an hour a day and study, read books, and do gesture drawings/30 second drawings. when you do these excersizes it isn't necessarily for the sake of accuracy, but to get in the groove of drawing human bodies. try to draw angles that make you feel intimidated, but most of all try to understand the structure of the body. if you understand the underlying muscles, how joints work and so on then drawing bodies will be 100000x easier! note me if you want some material to help you study. studying anatomy also will help you to draw clothes that fall on the body realistically!
As far as the drawing technique goes, I see that you did this digitally. I don't know if you used a tablet, but if you only have a mouse then drawing digital line art is nothing short of rigorous. If you did use a mouse then it was probably even harder to get good proportions. but, whether using a mouse or a tablet it is VITAL to take your time. don't be afraid to undo lines that are incorrect. you may undo a line 30x before you get it perfect, but through practice it will become easier. let me know if you used a tablet, and I can give you more in depth advice. as far as using flat colors go, since this was a reference I don't think its necessary to lay down shadows, but if you're going for some sort of aesthetic appeal then i would recommend adding shadows. once again, study anatomy in order to know how to place shadows correctly.
lastly, one side note I wanted to give you is about making our character fit into this drawing without the white background attached. I don't know if you used photoshop, but if you did then you can select the magic eraser tool and then click on the white background around her and it'll disappear. or, what you could do is set the layer that Bridgette is on to multiply, which would also make the background clear, however since her dress is white it will show through so that probably isn't for best.
All in all, this is a very nice picture and your character is interesting, so I hope you develop a comic with her or that you draw her more!
I agree on the anatomy thing, It's a constant work in progress. ;3~! I agree with all of the suggestions.
No I used a tablet, and Tradi inked it. Oh I didn't know Sai could do that oxo! I actually just like flat colours but I will give them more try!
For some reason, when I attempt shadows it doesn't work out, I'll keep studying it though.
Thank you for taking time to see this critique!
no problem. note me and i'll give you more in depth advice about shading, Sai and using your tablet! you actually cannot use a magic eraser with Sai, but you can at least set the layer to multiply and then color her blouse white on a layer underneath her,so that her blouse isn't see through but the white around her is see through, you know what i mean? and also i hope you have a merry christmas!