A person who knowingly drains resources of any kind.
A state benefit thief is a resource drainer.
A person employed in a role where they do very little work in exchange for a generous salary (usually large public organisations) is a resource drainer.
My little wallet drainer hit me up again for some new kicks.
A dick drainer is a female whos pussy is so good, that it drains all of the semen out of a mans body.
Chad: Bro, Stacy was such a dick drainer. I'm still a bit sore down there from how much I pumped into her
Geoff: Dude, TMI
Someone who depletes sniper ammo in an online gmae to prevent the enemy from using it.
Damn that Sniper Drainer, I finally get snipes and there is no ammo!
a woman who wants to have sex and/or gives head so much that she keeps her guy (or guys) in a constant state of being drained of cum
Angelina Jolie gave me three blowjobs today and then we fucked after that! She is such a ball drainer!
A friend, significant other, or acquaintance who won't stop texting you.
Adam: Dude your phone has gone off like twelve times in the last ten minutes.
Brian: Yeah that's the new girlfriend. She's a real battery drainer.
a plumber
My toilet has a leak. Better call my personal drainer