Is he using me?

K so my boyfriend has 7 kids. He works full time but it just isn’t enough. He has custody of 4 of his kids so they’re with him full time and in between the time his sister will help out with them on her days off from work but as far as financially it’s all on him. Their mom is on drugs so she doesn’t work & time again he’ll ask me for money. For gas, or he’ll tell me he’s hungry or say that he’s broke because the mothers won’t help him and that he’s paying all of his bills by himself even though he has his sister living with him. Sometimes I help him, sometimes I don’t. When I don’t, he understands. Maybe it’s because I have no kids that I just find it kind of annoying because it’s like no one told you to have all those kids and if your sister is working you should be making her literally forcing her to help pay a bill. But that’s just my unpopular opinion. It just annoys me when he asks sometimes because it’s like I’d never ask that of anyone else but at the same time I don’t have 7 kids that I’m responsible for.

Opinions?