Okay so...

Hey thanks for watching!
Before anyone says "It's 'Hip Hey!' not
'Hip 해'" It's
'Hip 해'. I understand
Korean, and go on Google
search 'Mamamoo HIP' then on 'Lyrics'
it's written 'Hip 해' so voila. A thousands
of memes were wrong. It's 'Hip 해' not 'Hip Hey' ;^;
[해 = Hae/He] I can't translate it to English sorry T^T

And if you want to know what the Korean words at 0:21 means
then here is the translation:
이쁘시 네요! = You're beautiful!
귀엽다! :3 = So cute! :3
And for Wow it's just Wow ;^;