companionate

adjective3

1. •
   Friendly, companionable.
2. •
   Pertaining to a (chiefly romantic) relationship that emphasises companionship and mutual respect.

   • Gradually it evolved from an economic enterprise to a companionate one—a free-choice engagement between two individuals, based not on duty and obligation but on love and affection. — 2017
3. •
   (historical) Designating a proposed type of marriage (or other partnership) in which the partners plan to have no children and take on no legal obligations to one another.