Definitely not a fern! Asparagus is a flowering plant, ferns are not; the two should not be confused.
Unfortunately common names are often not accurate descriptors of the plant itself as is the case here. Another common misnomer is calling something a palm when it isn't.
Errr . . . if they're not accurate, simple answer - don't use them! It isn't necessary to perpetuate lies and falsehoods!
Regardless, they like indirect sun or low light lots of cool humidity (a bathroom is not a good place because it gets too hot) keep it well watered and misted
