"A-Arnon, s-StoUOP! I'm Se-HEE-rheeius!" Twilight snort-giggles, furiously throwing hooves in an attempt to escape from being ferociously tickled on her back, until she had snot run out of her snout. Gross, but she had it coming. She's not even sure how he's managing it with one arm, but she's too busy flailing to figure it.