A tangasm is not a climax in the way we think of an "orgasm." There is no particular moment of release. The tangasm is not about how it looks, it's about how it feels. A tangasm is a moment of total connection coupled with full-body pleasure, bodies swirling with each other, breathing together, a union with the moment, your partner, the music, the room.
As to whether or not you can experience orgasms (awake or asleep) before you've started having sex, the answer is another resounding YES! Yes, yes, yes, yes, oh, yeeeeeesssssssss! Again, we're getting the feeling you're under the impression that your sexuality doesn't get ignited until some other person has sex with you. Not true.