YOU SAID:
want to grab a coffee after work
INTO JAPANESE
仕事の後にコーヒーを飲みたい
BACK INTO ENGLISH
I want to have a cup of coffee after work
INTO JAPANESE
仕事が終わったらコーヒーを飲みたい
BACK INTO ENGLISH
I want to have a coffee after work
INTO JAPANESE
仕事が終わってからコーヒーを飲みたい
BACK INTO ENGLISH
I want to have a coffee after work
That didn't even make that much sense in English.