Good Day Master Vander, Sir. a three day continuous submission sounds exciting for both of You. i have afew ideas that You might consider for Your new subbie. i don't know the nature of Your relationship but it sounds like you are both fun and up to these. Most are not original, i served a Dom couple for awhile, part time, and these were required of me at when in Their house.
1. naked for the entire 72 hours while in Your apartment.
2. first act is to shave completely below the neck.
3. on her knees when ever she is in the room with You.
4. multiple enemas, in Your presence, until the water released is clear. (Very humiliating). The toilet may be used but no seat is permitted..
5. asking permission to pee, and again, done in Your presence in a bucket not a toilet, and made to drink lots of water. Half the pee from the bucket from the last pee is mixed with the water for the first glass.
6. displayed daily at least on webcam performing for You, either dance, erotic show with dildos or performing sexually for and with you. Masks are permitted to protect identity.
7. spend some time with Your cock in her mouth, not sucking, just holding it in her lips, while you watch TV, do work, or read the paper.
8. Very skimpy outfits when going out of the apartment, no underware of course.
9. a naked ride on the interstate so the truck drivers get a nice show.
10. spend some time at an ABS (adult book store)/sex shop, choosing outfits and toys.
11. oral sex in an ABS video booth with a glory hole so she can be watched through the GH.
12. Nipple clamps alwasy add so much to the feeling that a subbie is owned.
Running out of time, but i hope this list helps.