Thelonius Jackson: No way! Are you stroking me right now?
Tyrone: No, I'm being completely serious. Trizzle is in the hospital.
Thelonius Jackson: Word.
If you're in polite company, you would use the subtle word "stroking" instead of the blunt terms "masturbating" or "wanking".
Cheryl: No, I couldn't go in. He was busy.
Mum: What do you mean "busy"? If he's busy, you can still take it in, can't you?
Cheryl: No, he needs his privacy. He was, um... busy stroking himself, Mum.