The title you're referring to, " 30 Days with my School-Refusing Sister

Based on the title structure, this appears to be a reference to a specific (eroge) or interactive game, likely titled something similar to " 30 Days with my School-Refusing Sister

Day 30: The last day of my “30 days” observation. Lena wore a clean hoodie. She packed her own lunch—first time. She said goodbye to me without irony. And at 3:30 PM, she came home and immediately fell asleep on the couch.

Gradual exposure therapy works better than brute force. A 5-second victory is still a victory.