If a transgender male  has a relationship with a non-transgender female, are the a straight couple or gay?

Neither.  Just confused

They are a straight/heterosexual couple because he is male regardless of his birth genitals, and she is female.

Lesbians because the trans man is just pretending to be a man.

A man and a woman together is a straight couple. 

Actually they could be bi or pan so it might not be 2 straight people but you know what I mean. 

The transwoman would call them lesbians. The fun of it for them is to LARP, colonize, and invade the lesbian community.

But they're frauds. They're a straight couple.

A transgender male is a man. If he has a relationship with a female, then they're a straight couple.

When a male and female are in a relationship, we consider that a straight relationship.

Transman?