The 'RIP' singer explained that she has often worried about some form of creature coming out of the bowl.
"I always feel that when I go to the toilet that something's going to come out of the bottom," she is quoted as saying in The Sun.
"I have this thing where I think this tunnel must start from somewhere and sometimes I think, 'What if something comes out of the toilet?'
"That's been one of my fears. I always make sure I put the light on when I go."
The star recalled one incident where she confused a former boyfriend by falling over late at night.
"One time I tried to use the bathroom in the dark and I missed the toilet and I fell on the floor.
"I was going out with someone at the time and I was trying to be all smooth and cool and didn't want them to hear me going to the toilet.
"So I walked in and couldn't find the switch, so I went to the toilet and I fell on the floor.
"He woke up and he said, 'What happened?' and all you could just hear is a crash. I said, 'Nothing!'"
Rita Ora released her debut studio album Ora yesterday (August 27).
She recently revealed that her mother often embarrasses her in front of mentor Jay-Z.