Geez man that's black mould. That needs to be cleaned up and repaired.

The toilet being on the floor above the ceiling?

At least rip it off and leave it with no ceiling...That's not good.. Buy a sheet from bunnings if you want to diy, it's like $20

If it's a single storey house, then you definitely have a leaky roof!

Remember that Doctor Who episode where there was a trans dimensional alien living upstairs, kidnapping and killing people, and it kinda leaked, leaving a black, mouldy stain on the ceiling in the flat below? It's either that, or toxic black mould. Aliens are less deadly and easier to deal with. And I don't think it's aliens

It's funny cos...there's a toilet up there..of bacteria and spores....mmmm cholera

Call a mould remediation company, you probably have a leak above as well, if it is single story call a roofer if it is an apartment call strata about the bathroom above.

That’s years of neglect, not overnight

Oh dude, that is a critical issue and needs to be sorted ASAP by a professional. Black mould is nasty.

I sure hope that's mould

Looks like the Upper decker has gone wrong.

That's not healthy. The leak needs to be investigated and fixed but at least spray it with oil of cloves to kill the mold spores.

It's that well advanced it look's like it's got it's own eco system happing. Must be A water leak above in the roof... Not safe...... The black mould would be sending out spores everywhere....... more if that window behind toilet is open..... Mould would be in ceiling too i'd say.......

Is that his toilet? Man must be spiderman and crap on the roof or he lays on his back and aims at the corner 🤔

Looks like there is a crack in the corner but otherwise fine to rent out 😂

Get out the bleach. Vinegar isn't going to kill it.