Sharp eyed and artistically literate 2channers spotted this “tribute” in the illustrations to the fourth volume of the novel 人類は衰退しました / Man Has Decayed, by noted eroge scenario writer 田中 ロミオ / Romeo Tanaka.
The garden scene is “View from My Window, Eragny” by Camille Pissarro. The other artist’s name seems to elude even Google.
The illustrations are actually by the relatively obscure 山﨑 透 / Tooru Yamasaki. No wonder he’s obscure?
Tribute or plagiarism? As no attribution is given and the resemblance seems more than passing, might we think plagiarism?
And this leaves aside the question of how 2channers came into possession of such knowledge…