Giving a hand 

1: helping someone with something
2: masturbating someone until they ejaculate
3: giving a round of applause

in the porn industry, you will see some hot bitches or hot guys giving a hand to their partner until they cum

Giving a hand by curtis450 May 23, 2019

hurt like giving a knife a hand job 

Self-explanatory idiom.

When I got spurned by Cheryl, it hurt like giving a knife a hand job.

hurt like giving a knife a hand job by LeanBeefPasta November 30, 2010

why are you giving me a handjob? 

A means of expressing confusion or contempt.

Derived from any cookie-cutter porn situation in which a female character disguised as teacher/friend's hot mom/friend's hot sister/nurse/doctor "unexpectedly" gives the male character a handjob.

Fritz: Dude, I boned your mom last night. Ah yea.
Ben: Dude, Fritz, why are you giving me a handjob?

why are you giving me a handjob? by Beefy McNasty January 8, 2008