Hide them

You decide you can wrap them up in your dirty clothes. That way, when your aunt does the washing she probably won't find them. They'll be cleaned in the washing machine and all evidence of your misdeed will be washed away.

You wrap the panties in your wet pants and stuff them into the hamper.

You turn on the shower and get the water temperature right, then step in.

I've really got to get a handle on this. I'm a guest in my Aunt's house. I can't be cumming in her panties. It's not right.

It felt so fucking good though.