kink, piss
pissing myself makes me horny so I guess that's sexual, but at the same time it's also just sensorially extremely comforting and stress-relieving and it creates certain happy thoughts in my mind, so I guess it can also not be
kink
to be fair I definitely consider it sexual, the same way I do desiring an owner to look up to, I apply the non-normative definition of that.
but part of the thing is that people tend to jump to certain undesired assumptions when they classify something as sexual (especially with unknown kinky stuff), which makes it a bit less practical to use that word for some stuff