pg.1-16: probably from OTOKO MATSURI 2 https://mitsuwabldg.booth.pm/items/518115 https://alice-books.com/item/show/6100-2 https://www.pixiv.net/en/artworks/62819173
pg.17-32: probably from Yuujuu Fudan III https://mitsuwabldg.booth.pm/items/1007883 https://alice-books.com/item/show/6100-21 https://www.pixiv.net/en/artworks/70631293