Leviticus 15:16 "When a man has an emission of semen, he must bathe his whole body with water, and he will be unclean till evening"
Nobody else is present. As opposed to the distinction when a female is present two verses later.
Leviticus 15:18 "When a man lies with a woman and there is an emission of semen, both must bathe with water, and they will be unclean till evening."
Emission of semen is different in this chapter than that referred to in Deut 23:10 as merely a nocturnal emission.
Deuteronomy 23:10 "If one of your men is unclean because of a nocturnal emission, he is to go outside the camp and stay there."
Therefore I conclude that these verses refer to 3 different types of emissions. That which one has with a woman (Lev 15:18), that which one has during the course of sleep (Deut 23:10) and that which one has that is self-generated (Lev 15:16).
These proscriptions relate to cleanliness. They do not relate to sinfulness. For example, rape is sinful, but it also related to cleanliness.
These proscriptions relate to cleanliness. They do not relate to sinfulness. For example, rape is sinful, but it also related to cleanliness.