A diaper fetish, also known as diaper play or baby play, is a fetish wherein one partner not only dresses in diapers, but usually also behaves and is treated like a baby. There is another group of fetishists who are simply into wearing diapers and get off by that alone. But most of the time this is a role-play fetish.
In the typical role play the "mother" will powder, cream and change the "baby", swaddle and hold them, even deal with their excrement (which may be a fetish for some people in and of itself).
Diaper play specifically addresses the need that we all have to be protected, given affection, and taken care of even when we feel helpless. This doesn't necessarily have to take a sexual form, but it can be a release by creating a safe and happy experience.
More creative roleplay ideas here:
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