"Then that is too many chocolates!"

Okay, make he should stick around to make sure Shiro doesn't die from engaging in some chocolate-fulled insanity. Because you just never know. Normally he'd awkwardly decline but if it keeps Shiro from causing himself problems, fine, he'll sing.

"Okay, okay, what do you want me to sing?."

Yeah, he'll sing that like the Disney weirdo he is. Enjoy your kid's lovely dulcet tones, Shiro.