In Chinese, there's a word to explain a state of relationship, '路人' originally means people on road, when something happened, '路人' is kinda character that won't join the trouble itself, but watching it.
But now, '路人' has a meaning of 'not friend', you may know him, or he know about you, but you won't have deep relationship, they just walk by your life, but not close to you. is there an English word to represent it?
looks like it's not 'acquaintance' because they may be stranger of each other.
some example of '路人'
After entering the aristocratic mansion, it was deep as sea, the one true love is _____(passerby?).
description: she can no longer find love because she became a slave.
he's just a ____(randomer?), I don't know him.
description: someone is trying to clarify the relationship
don't be too serious when playing with ____(random teammates?).
description: game matching system sometimes gives you bad player.
why many people choose to be like ____(stranger?) after breaking up?
description: they choose to forget each other instead of continuing to be friends.
A bunch of _____(bystanders?) who doesn’t know the truth are squatting there.
description: a little bit derogatory.