Why Did He Steal Our Baby Name?

So my bf and I are expecting our first child in Feb..we had talked about having kids in the past and had names we liked and so on. Well anyways this guy, who I won't call a friend because he's more of a pest, ended up knocking up some stripper, which he already has 3 kids from 3 different people so I almost feel bad for her. This dude has small man syndrome for sure and literally goes out of his way to copy my bf...his haircut, his clothes even down to his extracurricular activities. He's always just showing up at our house and sits down and tries to talk when we are clearly not interested but he can't take a hint. Well miraculously and ironically they find out they are having a boy and STEAL the only name we had picked out for that gender, stating he already told us he was using that name before...what before we even got pregnant?! oddly after WE told you guys thats the name we wanted?! fuckin garbage!