yess I was thinking that too at first but like you said, after rereading the first chapter I got it. He lived as a boy all the time but he remembered his last life as a girl only later, so is understandable that he "likes girls" or he finds it more normal
I don't get why he end up being with the hina girl because in his first life he is a girl so why not go with a boy? but I mean idk I guess not judging