How do I ask for oral sex from a nervous guy?

C

Hey ladies, I have a question for ya. How can I ask my boyfriend for oral sex? We have been together for a year and some change and we just signed the lease on our first apartment together. I love this man, but our sex life, well... lacks luster.

I regularly go down on him and have kind of hinted that I would like it if he reciprocated. But he gets really nervous and changes the subject or does something distracting, so I don't push it. I just want to have a conversation in a way that doesn't make him nervous or scare him off.

It's not a deal breaker if he doesn't do it, but he always avoids the topic altogether. I'm afraid if I outright ask, "Hey, do you mind going down on me?" he might freak out or shut down. Do you guys have any advice?