I just got asked out-I said yes, and he calls me "boo" what can I call him? Needs to not be sappy?

Well I call my bf alien just to tease him and he calls me big head so anything that suits you actually just think about what his personality is like and try to pick something that resembles it like my bf he moves around alot and is always jumping so I call him buzz bunny lol but yea idk what else to say

Well something that's not too sappy but still says I care and goes with boo would probably be like babe, bae, hun, or love. I would refrain from baby, sweetheart, angel or anything like that would come on too strong with you guys just starting out.
We've all been there :) Best of luck to you guys!