Hm....it's a very interesting topic. I have a feeling this will turn out redundant and I will try my best to not let it be but..here goes anyway.
One thing I will start off and say though is...with a lot of the costumes...the materials used make it look...well for lack of better terminology...costume-y.
I think...it wouldn't be as huge of a discussion point if they were made out of more practical materials like most of the typical lolita wear is. It's usually quite durable, can take a stain or two and handle being worn time and time again without falling apart or looking like you just pulled it out of a box. This isn't to mention a fairly high resale value. (With high quality cosplays this is true too, but I'm not going into that one) I know that a lot of lolitas put huge emphasis on brand and with brand...comes a hefty price tag. Is there anything wrong with Bodyline and FanPlusFriend? Of course not. There's just a line between what could be considered the "proper" lolita and costume.
Take lolita in anime for example.
Rozen Maiden, Pandora Hearts, Touhou Project, even Vocaloid and Hetalia have taken elements of lolita in a lot of their character designs. That's not even mentioning Chobits, Shaman King and even the Alice in Wonderland inspired animes such as Alice in the Country of Hearts. There's so many, it would be quite easy to take it and incorporate it into something that looks more like clothing and less like the costumes that the community has complained about so often.
There's absolutely nothing wrong with buying and wearing things that make you happy or that you find cute or what not. I see nothing wrong with wanting to incorporate some of the elements that you're talking about.
But...in my opinion, the "rules" were put in place so that the fashion would remain fashion and not turn into cosplay. There's a huge difference in walking down the street in a typical coordinated lolita set and that brand new shiny Chii cosplay.
I think the point I'm trying to make here is...if it's what you want to do...go for it.
You've just got to understand that there typically is a difference between the two and it's not a line that many lolitas ever like to see crossed.
Do I have a problem with it personally?
If it's done well; of course not. I take no issue or offense with it. I'm sure there's plenty of things that could work nicely. Would I ever do it myself? Probably not.
I'm sure everyone interprets this differently and I'm certainly no expert; I've only done a considerable amount of research on this and similar topics. I take no real sides here.
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