Last name debate.

Bf demands that the baby has his last name, but being that our relationship is iffy I feel that the baby should have mine. It also kills me to even think about it because he’s told me to get rid of the baby several times at 9weeks but now he has so many demands and requests for the child he didn’t want. I’ve agreed to hyphenating our last names he said no he wants his only. He’s also tried proposing..again so we all have his last name but I said no!