I guess Aella will only have her spider to play witH

I'd have to say that even in the Slytherin dorm she creeps people out because I picture odd glass cases stacked around her bed and in each is an unusual spider of various sizes, colors and shapes. 

Usually hiding somewhere on her body is her favorite spider Nos 

She is fascinated by death and because of it is fond of talking to the school ghosts. When she dresses in clothes other than her school uniform she prefers an understated goth look and somber colors. 

Some at the school have heard her alone in the music room playing the huge piano and singing muggle songs.