Okay, so ever since I got into BTS, one question has bothered me to the bones and I need it answered....

HOW WOULD KIM NAMJOON FROM BTS SPELL THE WORD 'COLOUR'?

I'm wondering this because it's spelt differently in different countries.

If Rapmon taught himself, it would be likely that he uses common English spelling, colour.

BUT, I've noticed Rapmon has an American accent, and that spelling would be color.

I've just been SO CONFUSED for the past how long. 

PLEASE ANSWER AS SOON AS POSSIBLE! THANK YOU!!

credit to owner.