To perform a service, or help someone & unexpectedly getting screwed in the process. Often times when you hear someone say "You give them an inch & they will take a mile" - this is referring to someone who got suckerfucked. There is no sure way to prevent a suckerfucking, as they usually come without warning, however it is a good idea to stay away from habitual suckerfuckers as they are known to continually suckerfuck unsuspecting victims.
worker - "This customer just tripled his order at the last minute and then bitched me out to my boss for not having speedy delivery"
co worker - "Dude you got suckerfucked"
Denice - "Hey Timothy want to come over to my new house for dinner?"
Timothy arrives to Denice's house only to find out he got suckerfucked into helping her unpack all of her things.