Would the simple description "Exploring" be sufficient? I wouldn't worry too much about getting attached to defining anything. Just live day to day and go with the flow. Que sera sera. Focus instead on needs and feelings and just keep talking it out. I believe that the worst thing two people can do to a relationship is try and fit it into some kind of box. Expectation breeds disappointment.
“As I am sure any cat owner will be able to tell you,
someone else putting you in a box is entirely different
from getting into a box yourself.” —bisexualbaker