"Am I?" For a moment he kept his expression neutral, then sighed and gave in. "Fine, I'm your friend. But this one... Has a tail." And is adorable and fuzzy, but those words couldn't seem to leave his mouth.
Other options:
no subject
"Am I?" For a moment he kept his expression neutral, then sighed and gave in. "Fine, I'm your friend. But this one... Has a tail." And is adorable and fuzzy, but those words couldn't seem to leave his mouth.