The given tag "18-porn-guy" seems to have the following meanings:
1. Age of performer - It suggests that the person in the video is an adult male who is 18 years old or above, which is considered legal age for participating in porn content.
2. Gender - The term "guy" denotes that the performer is male.
3. Category - The context implies that this is a porn video featuring a male performer, specifically an adult one.
So, the tag refers to an adult male performer who is 18 years old or above in a porn video