User blog comment:PockyPrincess/How Did You Find Pretty Cure?/@comment-78.147.57.106-20120607220716/@comment-2.98.241.62-20120719103127

Found It! It's:

Len Kagamine's Embarrassing Moment! [English fandub]

(Copy this title and see this vid in YouTube! Its funny :3)

Anyway I search for pretty cure and accidently watched Futari wa Pretty Cure Max Heart OP and it kicked off there. That's how I found PreCure.