Night: Relaxing intro. Short and sweet.
Party Around: Cool upbeat groove. I really like the bass.
Vs Stranger: I like how this is simultaneously groovy and menacing. Fits how they're still at a party as per your description.
Song that plays when you've messed up: I think this is a really effective game over jingle. I could see that ambience at the end going on and on until you hit "Continue" or something like that.
By Water: This is pretty. Nice guitar.
Vs. Loneliness: I like this calmer take on a boss theme. Really fits the description you posted too.
Pier: Like the water sounds. A satisfying end.
Great work! Loved reading the story too.