Prolly 'cause your mind doesn't know what cool is.

[The lad sticks his tongue out partway to the Marshall, showing him just how flat he can make it before turning on the "ol' raspberry".]

Monkey is a great name! People are gonna' know me as Monkey D. Luffy, the King of the Pirates! [He grins brightly at the thought, crossing his arms and standing confidently as he preaches on.] It looks good on wanted posters, too!