In need of some opinions!

Alright ladies, I'm going to be hooking up with a guy tomorrow and he just asked if I'd have sex without a condom for a bit and then put it on later. Now I'm not on the pill, I've never had sex without a condom, and according to eve my fertile window doesn't start for another four days. I'm just looking to see what your opinions are and if anyone else has had experience with this. Thank you!