Long time lurker first time poster. The Muramasa guy has also listed versions of 1943 jacket with fake Tenderloin patch (well I guess Levis and Sweet Orr inspired with the tug of war design?)
https://zenmarket.jp/en/auction.aspx?itemCode=1159072045
This seems to be the dude https://www.instagram.com/muramasa_glove/?hl=en and https://www.instagram.com/muramasa_jeans_factory/?hl=en
Rakuten store (no jeans for sale on there though, just Mickey Mouse logo'd fake Rolexes and box logo tees) https://item.rakuten.co.jp/royal-west/c/0000000121/
From his Facebook he does genuinely seem to be in Osaka https://www.facebook.com/yuya.shiozaki.5 and likes Triathlon a lot.
I think Takuya Kimura comes into it because Kimura seems to wear a genuine obscure Japanese brand called SC Subculture https://sc-subculture.jp.
Some of the Muramasa stuff is also sold with a Subculture patch and pictures of Kimura (eg. https://zenmarket.jp/en/auction.aspx?itemCode=n1159212942)
SC Subculture's boss' instagram posting about Kimura https://www.instagram.com/p/C1vTqR9Pckn/?next=%2Fbluegodzi%2Ftagged%2F&locale=在线定制塔吉克斯坦TEF证书联系{威信%2BTG%2F飞机%3A%40buth2788}sjwNH%3F%3F%3F%3F%3F%3Fѧ%3F%3FƾSwQuO&img_index=1 not sure if Kimura actually talks about the brand on his YouTube or is just wearing Subculture in the video.
I think the Kiwami items are intended to mimic Neatstyle as they have the same blank patch with just WWII and waist size. I find it kind of strange/funny cause you wouldn't think Neatstyle would be big enough to be worth bootlegging. What I do enjoy is that he seems to use a bunch of different red tabs (Tenderloin jacket has IRON'S red tab).
Although it all seems a bit fishy to me, they do seem to sell for reasonable money eg. this used Muramasa jacket on 2nd Street (which also shows inner tag) https://en.2ndstreet.jp/goods/detail/goodsId/2340110413269/shopsId/31327 and some competitive bidding on Y! as mentioned above.
