I think something that is really humiliating can be simple and normal stuff rather than kinky things. For example I would be way more humiliated to have to dance and sing a song for a Mistress than to suck a dildo or anything like this. Basically things that are usually funny for others are most humiliating I think.
I feel like many people actually underestimate things like this and how effective they can be. It doesn't always has to be kinky.
Examples:
-singing
-stripping seductively
-dancing
-humiliating poses when texting you
etc
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