One can be peckish if hungry.
Cupper-cup of tea
Cuppa-cup of coffee
In your cups-drunk
Why can’t I be cuppish if I’m thirsty.
Lemme see how peckish works with the other suffixes.
Peckish-
Pecker-hmm 
Pecka-double hmm
In your pecks- well, that sounds violent.
Just cannot be done.
My bad.
You peck at your food, like a bird. You don’t cup at your drink. I think “animal taking small drinks” would be lapping, but “lappish” is terrible. Maybe sippish?
You drink like me it’s more “Drippish”
Don’t the cool kids say sitient, or something?
Never heard that word. 
Now considered obsolete, with its last known usage around the 1870s