Three consecutive nights maximum. The lease was very clear

I rent a small but expensive two-bedroom apartment with my close friend from college, Sarah. When we signed our formal rental agreement last year, we sat down and added a highly specific roommate clause to our lease contract to avoid any domestic friction. The clause explicitly stated that romantic partners or out-of-town guests could stay in the apartment for a maximum of three consecutive nights per month. We both signed it, agreed it was fair for maintaining a quiet, professional living space, and moved in.

Three months ago, Sarah started dating a guy named Dan, who works as a remote freelance data analyst. At first, he would just stay over on weekends, which was totally fine and well within our agreed limits. I always made an effort to be polite, gave them space in the living room, and kept our shared kitchen clean. But over the last six weeks, the dynamic has undergone a toxic shift. Dan has basically moved into our apartment full-time without a single discussion or notice.

He has his own set of keys that Sarah quietly duplicated for him at the hardware store. His clothes are taking over our shared laundry bins, his specialized premium protein powders occupy half our kitchen cabinet space, and he spends literally all day sitting on our living room couch in his sweatpants, watching TV and taking loud corporate video calls while working remotely. I come home after an exhausting 9-hour shift at my corporate design firm, looking forward to a quiet space to decompress, and instead, I am forced to walk into a living room that feels like Dan's personal executive office.

Our monthly utility and electricity bills have literally doubled because he leaves the central air conditioning and multiple high-end monitors running 24/7. The apartment constantly smells like his specific greasy takeout food orders, and yesterday morning I realized he had consumed the entire box of expensive organic coffee pods that I bought with my own independent money. He doesn't pay a single dollar toward our $2,400 monthly rent, he doesn't contribute to the bills, and he treats me like a hostile intruder in the space that I legally guarantee.

When I finally pulled Sarah into the kitchen last night and showed her the utility bill, suggesting that Dan either needs to start contributing exactly 1/3 of the rent or move back to his own studio apartment, she got incredibly offended. She slammed her coffee mug onto the counter and accused me of being a greedy, bitter, and unsupportive friend. She claimed that because he still technically pays rent at his own apartment across town, he is just a frequent guest who is spending quality time with his partner. Dan has completely ignored the situation, and now the atmosphere in our home is so radioactive that I lock myself in my bedroom the moment I get home.