...Blood or just oddly colored water? (or maybe even tea!) Maybe the author notes clarify that, but I can't read Japanese.

I think it's blood, but from a bit a way it looks like rose petals.

血風呂 = blood bath, so blood it is.

Guess it's "that time".

The buildings look messy

She's pretty tall.

Either that's a really big woman, or that's a small fucking tub.

That's some strange proportions and a bizarre bathroom layout. Does that bathtub even have a faucet or something or another?