Millie Perkins' House is the home of Grand Theft Auto: San Andreas character Millie Perkins and is located in the Prickle Pine district of Las Venturas. Protagonist Carl Johnson enters Millie's home during the mission Key to Her Heart, after killing Benny. Carl collects a Caligula's Palace key card from within Millie's home, allowing him to later pull off a heist at the casino. Millie's pink Club is often parked outside her home, and can be accessed after Carl's relationship with Millie reaches 50%.
If you kill Millie Perkins whilst on a date before she calls you wanting to take part in the heist, you can go into her house and collect the key after Wu Zi Mu calls you asking how your relationship is going.