URLs

• https://www.dlsite.com/maniax/circle/profile/=/maker_id/RG01519.html
• https://www.doujinshi.org/browse/author/28413/PROPER/
• https://www.doujinshi.org/browse/circle/17870/PROPER/
• http://anime3dcg.dojin.com/proper/
• http://anime3dcg.dojin.com/proper/pro/2dcg/2dcg.htm
• http://www.ksky.ne.jp/~proper/