So you know the Undertale fangame undercolombia by @Comic-juli . (If not go check it out before reading this)

Why don't I make something similar based on where I live!

Presenting...

UnderBRITAIN

the most cup of tea bottle of water experience ever made

Survive the underground filled with posh monsters with tea addictions and horrible teath!

Hopefully I think of something better soon.