I know this is gross but I haven't showered in a week

I know it's so stupid but I can only shower under really specific conditions and those conditions have not been met so I can't shower.

1. My dad must either not be home or be asleep.
2. Nobody can be in the kitchen.
3. It must be between 2:00 PM and 5:00 PM, or between 2:00 AM and 5:00 AM.
4. The dining table has to be pushed in.
5. My towel has to be big enough to wrap around my body and reach my knees.

The only time it's possible is early in the morning, but I've been waking up at around 5:30 every morning. Every day my dad is home and someone's always in the kitchen. Idk what to do. My hair is absurdly greasy and I know I stink but I literally cannot shower.