I need a pee really badly.

我很想。

Mummy, I need a wee.

，我要。

It is further possible that very private human activities like urination and defecation become erotically arousing to a fetishist.

进一步的可能是，每一种人类的私密活动，像和排便也会对恋癖者产生性唤起作用。