This is LoRA using LyCORIS/LoCon.

torogao:

A facial expression where the character appears to be in an ecstatic, yet quiet and unresponsive trance with their face almost melting in pleasure.

The cheeks look flushed, the eyebrows are slanted downwards towards the sides, and the eyes are half-open and moist, often staring into the distance.

heart-shaped pupils:

When a character's pupils are shaped like hearts. Often a sign of being lovestruck or experiencing sexual pleasure.