I know you can say, I'm dating him or her. Is there a verb (an -ing verb in this case) that can be used like that but for being in a relationship (the further step)?
Example:
Sam's not exactly a gay man. He's a transgender. So technically Mark'll still be ___ing a woman.
I checked the synonyms of dating. Bus as I expected they all mean dating, not being in a relationship.
(Idioms are also welcomed.)