YOU SAID:

yo, yall comin to th' partay tonight?

INTO JAPANESE

ねえ、今夜のパーティーに来ない？

BACK INTO ENGLISH

Hey, would you like to come to the party tonight?

INTO JAPANESE

ねえ、今夜のパーティーに来ませんか？

BACK INTO ENGLISH

Hey, would you like to come to the party tonight?