bleeder

noun

• A person who is easily made to bleed, or who bleeds in unusually large amounts, particularly a hemophiliac.
• A blood vessel that requires cauterization etc. to stop it from bleeding during surgery.
• Anything that saps a resource produced by something else.
• A valve designed to release a small amount of excess pressure from a system.
• A troublesome fellow; a blighter.
• A person who spends a great deal of time playing video games.