Maybe a Combat SecUnit. I imagine that the company would not want the ones that guard many very annoying clients to be "really murderous". Sounds like a lawsuit waiting to happen.

I listened to the audiobook and Kevin R. Free does an amazing job. The voice did bias me towards thinking of Murderbot as male until they made their deep disgust with the idea of having sex related parts clear. Between the role as a security guard, which scans male to me, and the narrator I can at least understand how I jumped to my conclusion.

I kind of think of those big egg shaped security robots that are around today as male. If they had the capacity, they probably would not appreciate that.

Murderbot would probably prefer we didn't talk about it, though. At all.