Another use of "whack attack" is the act of masturbathing multiple times without taking a break to relax or recharge. After the orgasm, one must sustain an erection and achieve another orgasm for it to be considered a whack attack.
Also, the word whack attack can be used to describe someone/thing that would cause someone to hace a whack attack.
Every time my roommate goes home for the weekend, I have a massive whack attack
That girl is really hot, she makes me want to hav e a whack attack