Beast does not seem like a kingdom to me. I guess we need to understand what an abyss is and who is presently in the abyss that could come out of it...... but a kingdom would be very hard to fit into that description in my personal view.
When a horn or beast is given a mouth, this refers to its leader (Daniel 7, Revelation 13)
I believe the abyss is symbolic language to indicate a kingdom re-arising from its deep destruction.
The Beast is both a man and his nation.