Don't Get Me Wrong, I'm a Serious Therapist!

Nineteen years after traveling through another world, I relied on the skills from my previous life to open a massage parlor to make ends meet. But can anyone tell me why each of my guests is weirder than the last? The elf princess blushed and said that my technique can make her magic power run wild. The knight of the beast-eared girl said that my massage is better than the strongest wine. Even the aloof dragon lady is here to stay! That's all, but can anyone explain why the princess of the kingdom, who is usually dignified and noble, and even has to be measured by the palace etiquette officer with a ruler when she walks, sneaks in in the middle of the night, complaining with red cheeks? And that! The legendary demon king who only wants to destroy the world! If you don't study forbidden spells in your Demon King's City, why are you lying here with a black face, staring at me with eyes that can kill someone, and growling through gritted teeth: "Recently... The performance of destroying the world has been too stressful, my back hurts..." Hello! This is a serious massage parlor, and additional Buffs are charged separately! "Mr. Linn... That... Can you hold it down for a while longer?" Seeing their identities becoming more and more outrageous, I felt... There seemed to be something wrong with my skills?