@Zeb
@Ren
Mlem: (adjective) the sound affect it makes when a tongue exits and re-enters the mouth. (Incidentally: I’m not sure there’s much of a sound anyway.)
Blep: the act of a cat sticking its tongue out slightly without realizing it, often for long periods of time.
Looks like internet speak that people have been adding, likely because they think it’s cute. On the images with the actual sound effect I imagine they fit but for other images we have things like
tongue out and
:p so why put extra tags for essentially the same thing?