Ne yo cracks in mr perfect
You're referring to the song "Miss Independent" by Ne-Yo, featuring Jay-Z, from his album "Because of You" (2007).
The lyrics you're thinking of are:
"I'm Mr. Perfect, I'm Mr. Perfect I'm Mr. Perfect, I'm Mr. Perfect I'm Mr. Perfect, I'm Mr. Perfect I'm Mr. Perfect, I'm Mr. Perfect"
These lines are sung by Ne-Yo, and they're part of the song's chorus. The song's theme is about a man who's trying to win over a woman who's independent and strong-willed, and he's proclaiming his perfection to prove himself worthy of her love.
The song was a commercial success, peaking at number 10 on the US Billboard Hot 100 chart and earning a Grammy nomination for Best R&B Performance by a Duo or Group with Vocals.