Need help finding the perfect word

I won't go into details but theres a really good chance me and this girl can become no strings attatched fuck buddies. Shes been hinting at it and I want to ask her tommorow. I want to ask her formally though, so does anyone here know what the correct wording would be for this type of relationship. I know the opposite of this type of relationship is a "Platonic Relationship". Any help is appreciated

Op here. Mission success. I just told her "I know this is strictly a "relationship" based off eroticism and I dont want it to change." Then we fucked while watching a lame ass porno on PPV. Thanks for all the help /lounge/ lol