Sleepwanking
Indulging in the act of masturbation while sleeping, usually performed by a man during a period of sexual frustration.
Tim has never had sex. One day, he woke up in his bed with a puddle by his side; he was sleepwanking.
sleepwank
The act of wanking prior to sleep, so as to improve the quality of your rest and also have an excuse to think of unfuckingbelievably hot chicks.
Griigor: I should have my good sleepwank and a nap.
sleepwank
The art of having a wank whilst sleeping.
"I had an awesome sleepwank last night dude"