Another Roommate

Another roommate moved in. Now there are two of us.
One is a bit tough. She tells what to do and what not to do.
The other one is just very laid-back.
She cares about nothing, fools around, and tries hard to reach the death.
I am not sure which one is new.
I am not sure if we can get along well, either.
We might be a complement for each other;
we could be a pair of conflict elements as well.
I don't really care.
I just need the tough one to be more stern.
I need her to control the whole room, and then I will just let go.