Mika hid in a toilet because he was nervous.
This act of cowardice happened last night, just before his 'comeback' 'gig' in London.
The 'Elle Me Dit' chart-topper chatted about this quite candidly (as quoted here), saying: "Were a little late on tonight, because I was supposed to do a radio interview, but I got so nervous I locked myself in my own bathroom."
"I was going to make an inappropriate joke here, but I won't," he continued, "essentially, in the end I just peed and got on with it."
We assume he was going to make a joke about shitting himself or something, but it probably doesn't bear thinking about in too much detail to be honest. Imagine Mika, covered in his own excrement. Smearing it on the walls, using it to write messages for the police to find when they are eventually called to the scene. "He was so unassuming," neighbours would say. "We never thought he'd do something like this."