How to get ex out from grandparents

I’m a 37F currently living with my grandparents. They’re getting older, and I help them with things around the house. I’m very independent, used to being alone, and I need my space to function. I have an ex (52M) I’ve known for almost 4 years. We weren’t really looking for a relationship at first, but it turned into one. He was always on good terms with my grandparents. Eventually, we started arguing a lot and it wasn’t working. He said he needed space, which I respected, so we cut contact completely for about 4 months. During that time, he quit his job (which I had warned him not to do without another lined up). Later, I reached out to him to see if we could meet up strictly for casual/physical reasons — no relationship. He showed up one day…and basically never left. About a week later, I found out he was getting evicted for not paying rent. Apparently, he explained this to my grandparents while I was gone one day. Since then, he’s been staying here and helping with home repairs (porch extension, flooring, pantry door, sink faucets, etc.). I appreciate the help — but I never agreed to him living here. I came home one day to find his former landlord picking him up to get the rest of his belongings. That’s when it really hit me: this wasn’t temporary anymore. I had already told him before all this that he could never stay here. I need my “me time.” I have severe ADHD and I’m extremely sensitive to other people’s energy — having someone around constantly makes it hard for me to think or function. This situation is seriously affecting my mental health. He’s been applying for jobs. I’ve taken him to interviews, and my grandfather even took him for a drug test for a janitor position at Amazon (he passed). My grandparents are allowing him to stay “temporarily” because he’s helping out and has nowhere else to go. No one asked me — it just happened. I’m charging him a small amount of rent, but he has no transportation, so I end up driving him places even though I said from the start that I wouldn’t. I do online sales (storage units) and I start my bachelor’s program in 8 days. I’m already overwhelmed. I’ve tried talking to my grandparents because I feel like he’s taking advantage of the situation. My grandfather even put an air mattress in the front bedroom for him, which honestly made me feel completely ignored. I understand they don’t want to put him out with nowhere to go — but this is not good for me. I helped him apply for low-income housing, but the waitlist is 1–2 years. He owes me about $2,000, which I’m letting him pay back over time. He smokes my cigarettes constantly. He says he’s applying for jobs every day, but nothing is changing. We are not together, and I’ve made that clear. He’s admitted he didn’t really consider my feelings and keeps blaming everything on “needing space” or “time to think.” What about my space? I’m not trying to screw him over or be cruel — but I’m also not willing to destroy my mental health to save him. My grandparents allowing this without my consent has made everything more complicated. How do I get myself out of this situation without being a heartless b****? Any advice is appreciated.