Nicknames for Dom

I'm super submissive my boyfriend isn't always super dominate but he will do it to please me.

I'm looking for something to call him in the heat of the moment. Daddy is the one word that wants to roll off my tongue but I find it really cringe and awkward haha.

I don't mind calling him Sir or Master but I don't think they work as well in the heat of the moment as they do in other times of play. I think King is cute too but also too formal not rolling off the tongue.

We recently somewhat opened our relationship where he will be allowed to have sex with other girls (following a few guidelines) and we will have FFM threesomes etc. Which has made me really horny and touches into my submissive side a lot. Which made me today think of Key as a cute nickname too like he is the Master Key that can open many locks and I'm just a little lock. Note: I hate the master key and shitty lock analogy when it comes to men and women sleeping with multiple people but the names are fitting for our situation mostly in a dom/sub setting. (Going through emojis made me think Hammer was quite cute and funny too)

Anyways mostly making this post to maybe find other dom nicknames that roll of the tongue feel free to post about your own D/s nicknames too.