a person who watches out for you when trying new and different drugs; usually thee experienced person or the person with less intrest in the drug; person who keeps you outta trouble
Bob- "Dude, I wanna shroom. Wanna be my caretaker?"
A person who deliberately causes the breakup in someone's relationship so they can have a go at the other person's partner. Usually they do it to a a close friend which makes them even worse.