Basically, most of these animes are light novel adaptations and the market for then in Japan is extremely saturated. So by making the title as descriptive as possible, there is a chance that it will catch someone’s attention as opposed to having a nondescript title.
It may not be realistic, but wouldn’t it be cooler if it did?
Like, seriously, nobody question when a character breaks physics when they flash step, shoot laser beams, or fly solely by their willpower.
Why should porn be subjected to realism more than non porn?