Devotion is easily proven with simple tasks. Swallowing your cum for me may make you gag, sure, but it's a simple price to pay to serve me. It's easy, really. A slurp and a swallow, and you've hurdled over the gross part and right into the "good boy" part. Think of CEI as a toy utilized to make jerking off more fun. Kinkier. More exciting. Plus... it proves how committed you are to me, and I like that.