Wife/KH wants less O's for me, but always gives in during sex

Alright, I am occasionally locked for weeks at a time, often not. We have lots of PIV sex, and I always must request permission to cum. She loves tease and denial, and we have practiced it many times. Especially when I am locked up, she verbally teases me, saying I cum too much, and the ideal amount is once every week or two (we have sex roughly 3 times a week). Now I usually struggle to fuck her well and not cum after about 4 days, especially if I have been teased, but that is beside the point, something I need to work on. For her part, she enjoys a creampie, but she also enjoys to tease and deny me. Usually, she seems pulled in both ways, wanting the creampie, but also wanting to deny my orgasm and get me desperate. My question is, are there any ideas on games or other methods she might be interested in that would help her deny my orgasm more often? Once she gets in a groove of a few denials, she is feeling powerful and keeps going. One method she used before that worked well was she promised me I could fuck her ass if I didn't cum for 2 weeks with sex and all. It put the onus on me to deny myself during sex while she taunted me about how nice it would feel to just nut deep inside her.