When a character is experiencing heavy emotions, pressure, or stimulation that leaves them feeling/appearing overcome with uncontrollable emotions (Including fatigue, joy, sadness, anger, etc).

I.e: A character who cannot handle pleasure or pain enough that it causes them to cry and express their feelings in a heavy, intense manner (Most notably through noises and facial expressions).

Details to look for (more often than not, overwhelmed characters will use more than one of these):

1. Tears.
2. Wide eyes.
3. Excessive blushing.
3. Open mouths, notably with teeth visible or the tongue hanging out.
4. Motion lines that give off the impression of shaking/trembling, and lines that invoke a sense of shock, surprise, alertness, etc.
5. Vocalized sounds of pleasure, pain, etc.
6. Panting (this can be shown through visible breath, audio, or sound effect text).
7. Sweat, drool, or other bodily fluids that represent the body being driven past a limit of exhaustion/use.
8. Slurred or stuttering speech.
9. Exaggerated facial expressions and/or body language.

Tag's associated with being overwhelmed: Tears , Crying , Wide_eyed , Flustered , Blushing , Drooling , Sweat , Overstimulation , Dazed , Panting , Breath , Exhausted , Open_mouth , Tongue_out , Trembling , Looking_pleasured , Eye_roll , Ahegao , Fucked_silly

Specific post examples using the overwhelmed tag: post #4689078 , post #4512899 , post #4474145 , post #4735770 , post #4526752