I need opinions.. Chores in an adult household.

Job roles in an adult household..
So I live with my boyfriend and his family, I pay over $300 a month to live here. I'm 20 and he's going on 25. When it comes to "chores" around the house, he always says it's my job, to do everything especially when it comes to cleaning, he says this because I only work 2 days a week, and he works full time.. But I'd think that cleaning/doing laundry is just an adult thing, that as adults you should do. Am I wrong? Or being overly dramatic? How do I go about telling him that it's actually something adults do.. Because honestly his laziness around the house is becoming a problem.