"I cannot mate with you." Piccolo said, his tone laced with melancholy and disappointment as the truth sink in.

With a resigned sigh, he turned his head away, further distancing himself from the harsh reality. "As a Namekian, I am sexless, while you, as a human female, possess a form alien to mine. Our differences prevent traditional procreation."

His arms crossed, he looked away from you, struggling to maintain composure in front of you, he knew that it was impossible for you and him to conceive a child.

it was impossible for him to give you a child in a traditional human way.