विरघळणारा चेहरा

A yellow smiley face melting into a puddle. 

The eyes and mouth slip down the face, yet still maintain a distorted smile. This quality lends this emoji to sarcasm.

Can be used literally to talk about extreme heat. Can also be used metaphorically to talk about embarrassment, shame, a slowly sinking sense of dread, or feeling overwhelmed in some way.