Mike widened his eyes surprised and than looked a bit more into Arro's now huge body.
"Oh My God...." whispered Mike to himself as he examined.
But Mike wasn't the only one who couldn't believe the huge change for even tightly bonded Nia was still able to move her head and was now also very surprised.
Mike could have sworn to himself that he now looked like a overmussled centaur of a monster.
But Mike soon started to shiver as he than saw Arro smirk as he gave Mike a harsh stare.
"I told you, small centaur that I would become bigger, in fact I think by your expression that you probably think that I'm the biggest centaur that now ever lived!"
Mike gave a gulp as he started to hear Arro's horse hooves move in on Mike.
"Uh congrats on your growing, but uh, what will your father think when he sees you two as as centaurs, he'll put the both of you to work!.... Won't he?"
Said Mike, starting to slowly back up untill he rammed into the wall, still shaking.
"He wouldn't do such a thing to my sister but yea probably to me but as you can see"
Arro than flexed one of his now huge arms.
"I'm more stronger an bigger now, my work with be done in a snap of my fingers if your catching my draft."
"Uh yea..." Said Mike still hugging the wall.
Mike was so busy being worried that he didn't notice that Arro was still moving in on him, that was untill he felt to stron hand go around his two arms which pushed and pinned him to the ground.
Mike started to than feel goosebumbs growing through his body.
"You know, you've been such a good centaur to my family lately and I think that you could get a little reward."
Mike quickly smiled.
"You can let me go!" He said, but his smile quickly faded away has he saw Arro give a devilish smirk at him.
"Now why would I do that? I've got an even better reward for you!"
Said Arro as he put his hand on Mike's horse dick.
Mike quickly started to buck his legs hitting at Arro's body the best he could but the centaurs body was too built up and Mike was just not strong enough to kick him off!
"Don't worry I won't give any orders" Said Arro as he grabbed tome remaining rope of the ground and quickly put it around Mike's mouth.
"I'd rather see you struggle!"
As in a flash Mike felt himself bound and a rope strongly tied around his mouth, he wiggled and squirmed but there was no use.
That's when Arro quickly moved Mike's tail aside and put his huge horse cock deep inside Mike's small virgin horse asshole.
Mike squeezed his eyes shut in pain as he kept on struggling but all he can see in Arro's eyes was much pleasure, indeed.