Alice liked using the Ancient Runes Classroom. It had an orderly, neat feel to it that relaxed her totally. The professor liked her and let her use it on the weekends, seeing as it was getting too cold to go outside and play her guitar. Her fingers had turned red raw from trying and the professor took pity on her. Ever since, she used the classroom whenever she got in a musical mood.
She had found the broken banjo in the room of requirement. It took a few sleepless nights to fix it, a little bit of her money to replace the strings, and now she had a new toy she could not wait to try out some more. She was careful on her way to the empty classroom, knowing if one of Grindelwald's people found her they would confiscate her perfectly good banjo. She had to watch her step carefully.
But she arrived without a hitch, and she set up to make herself more comfortable. She had found some scented candles in Hogsmeade and had been addicted ever since. So she set them up and lit them, sweet aromas of baked goods alighting onto the air. Then she spread out sheet music across the floor and pulled out her banjo.
She plucked the strings, marvelling in the difference in sound this instrument offered in contrast to her guitar. It was more folk-y, and folk art art was her thing. She melted into a musical oblivion, soon forgetting the need for discretion as she lost herself in the music.