Okay, um...

Homunculi are created using something that equals the sum total of a human body. This can be a variety of things, but the important thing is that the process causes it to take the form of a human body.

All homunculi are, as a result, physically human.

The Church does not consider them heretical and even has some of its own. Chapel, the girl I sketched up a while back, may even be one herself.