Mike is bisexual, and he wouldn't have any issues with a non-binary person. :]

But marriage!! Is an entirely other issue for him as someone with AvPD. He struggles a lot with keeping relationships, he can be a little flighty and the closer he is to someone the more likely it is he'd completely run off to avoid any potential conflicts. Maybe one day if he ever gets a therapist... but as for right now his romantic life usually ends up with a lot of short lived little flings before he runs off.