For me, climax of session is eruption of precum.

Whether I’m doing Aneros or Aless, I don’t feel I’ve really arrived till I have a release of pc. Do others have this experience? That usually only happens after the 20-25 minute mark. Before that I have some sublime p waves or dry os. Not complaining here. But when the pc erupts out I feel that’s like my high point and after that I can leave my session. IDK, unless that’s not precum? Could that be? Could it be semen? I’ve often wondered. But pleasurable it is, for sure. I’d be interested to know if others have this experience. 
to explain. It’s not necessarily a lot of precum. But it’s suddenly there after I hit a jackpot in feelings. It doesn’t feel like a traditional O. Where you have to go thru a refractory period. In fact you can still be up for more.