Sexual activity 'hanky panky' involving at least one person called Frank/Franky/Franko and both people have Wanks.
"Hey baby, I think you're amazing. Feel like some Franky Panky Wanky? I promise I won't respect you or myself in the morning."
Receiving a handjob from your partner while they are wearing a budget Frankenstein mask
“Yo bro, last night I had the most epic Frankie-Pankie Wankie, it was an utter monster wank!”