R18 has spelled her name as "Karen":
http://www.r18.com/videos/vod/movies/detail/-/id=11arm346/?i3_ref=search&i3_ord=1
I guess "Careen" was the spelling from the movie's credits? (I guess you own the movie...)
"dballzz"was also curious almost three years ago:
https://www.akiba-online.com/thread...ew-black-ones-too.31924/page-427#post-3086885
Non-star (I mean, porn actresses who are not famous) Caucasians who appear in JAVs can be obscure. You may be able to find other JAVs where this woman has appeared, but I doubt you will get a fuller name that this provided first name. (If you click on "Karen" on the R18 page, a bunch of other JAVs come up, but the only way to tell if the same blonde is featured is to go through each listing.) Fact that this movie (ARMD-419) is from 2004 makes this one even more difficult, because that woman is most likely long gone.
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