his art is very old (like, decades old), but he has recently returned to Pixiv.
Surprisingly, nothing has been lost from THIS gallery back in 2011, so I don't think there're many lost works from his Pixiv during these 10 years. However, there're big gaps in his gallery (based on the series number of his work, basically most artworks below 700 are missing); and since his website also go down, I can't find these pictures.. If you have any information about them, please let me know.