Pitch Perfect: Singing in the shower HD CLIP

What’s happening in this Pitch Perfect movie clip?
Beca (Anna Kendrick) takes a shower singing Titanium by Sia. Chloe (Brittany Snow), who is taking a shower next door with a guy, suddenly shows up behind her. She tells Beca that she absolutely has to audition for the Bellas. Beca is not very comfortable because they are both naked. Chloe asks her to sing again to see if their voices match.