When you're confident about something to the power infinity you answer with a Yuush.
An essential word for people who keep questioning you ! *eyes rolling*
For example :
Pessimist : Are you sure YOU can do this?
You : Yuush ! Is there even a second thought to it ?!
The best person ever, if you are friends with Yuuki then you know how awesome he/she is! they are great, sexy, kind, brave and they have courage. Yuuki may sometimes feel down on themselves, be kind to them! All Yuuki wants is a kind loving friend! (i heart yuuki)
Girl: Look it's Yuuki!
Boy: Yuuki is so awesome!!
Girl 2: Eee i love yuuki!