Voyeurism
The practice of taking pleasure in observing something private, sordid, or scandalous. this can be for a person watching a sexual act being committed by others with or without their knowledge often with the person watching engaging in masturbation. Also used for people who gain satisfaction/happiness from watching the person they like excessively.
![My Lover is the Girl Next Door / 恋人はとなりのお姉さん [発情期] cover](https://3r21zkocdpp9f.doujindistrict.com/book_thumbnail/cd9508fdaa5c1390e9cc329001cf1459.jpg)