Going to school would be the smart thing.

As fun as it would be to continue the absolute sexual wonderland that is now your life at home, you realize it would kinda just blow up in your face if you just fucked your mom and sister forever. Like you were in your senior year and were on track for a good college so just missing days for no reason would be kinda dumb. Also if you just have non stop sex you might end up getting numb to it which would make it all pointless. Not to mention you have been so self absorbed with your sexual revolution that you haven't spoken with your girlfriend all weekend, and dodging her with no explanation would be a dick move. Also your sister is in the same year as you, so if you need to fuck you could always just sneak off with her for some fun.

You explain to your mom and sister and they seem a bit disappointed but they get it. So you wash up, all together of course a good shower threesome is the best way to start the day. Your sister comes in as you are getting dressed, and she looks like a absolute whore. She wears a bikini top that looks two sizes to small for her massive tits, and barely cover her nipples. her bottom half is a thong digging into her pussy, covered by a pair of black sea through tights that can't of hiding anything. A cap on her blonde head read slut in big bold letters proudly declaring what she was.

You look her up and down growing you absurdly long and thick cock twitches, which when flacid it reaches well beyond the knee is like a fire hose cracking like a whip. You say to her "You seriously are going to wear that to school?" She walks up to you pressing her hands on your chest and gives you a kiss, her massive bust pressing against you. Then she steps back and says "Well of course all the naughty bits are covered, mostly. Besides I need to make sure my master has easy access to his property." She then pulls the see through tights down past the globes of her ass and pulls the thong tight on her glistening pussy, she is absolutely soaked just from being in front of you. She looks at you waiting for your approval or dismissal.