Duolingo is more than just a beneficial tool for those wanting to master a new language. It has also gained popularity among language lovers. However, regrettably, it seems that even this popular platform is not exempt from the infamous Rule 34 dictate.
Many have stumbled upon that Duolingo + Rule 34 fusion exist. It could come as a surprise, but evidently, there are actually fan-made illustrations based on characters from Duolingo which adhere to the infamous guideline stating that "if it exists, there is porn of it."

Rule34 If it exists there is of it