It's a linear text-based game, meaning a continuing story. Then there's sandbox games like Whoremaker, Young Maria, or The Company. Sandbox games have the luxury of having lots of clicking or repeating content over and over until a certain measure is met, thus creating more content. With a linear story, it's closer to a book that can lead to multiple endings. You follow a branch and the story continues onward from that point. You don't keep repeating content until your (insert stat) is high enough. Balancing pace, content, and use of images in this style of HTML games is tough. "Less words, more pictures" is definitely easier said than done.
Even with that aside, pictures/gifs of a girl being reamed can only say so much. Context in text-based games matter, probably more so than most other adult games out there. To reiterate, it's a text-based game. You're supposed to read while the pictures remain an accent to the given context. Which breaks into your second point, the amount of text written is to create a detailed scene to make up for the immersion lost in the varied imagery.