In my opinion, the reason why this VN is so popular is because of its dialogues. This is the only game I know of where you can find obscene words like "Photosynthesis", "Nihilism", "Chloroplasts", "Diploid"...
I still remember when I read the word "Epitome"... I almost got a hard-on.
You reached the epitome of gratification and revelled in the sensation while Mr. Xavier described the allure of art.
No but on a serious note, this vn does have really well written dialogues, lots of words i have never even heard. Plus some scenes are pretty informative too, there is some research put into what is being written and presented. Like the Art class scene, the whole thing about Ares and Aphrodite was something i didn't know. Not in particularly used to reading about gods anyways but it added an authenticity to the art class. During sex ed too, the information part is well written.
I don't know about others but i like the informative parts of dialogue in scenes.