Mika had his best kiss when he was 17 - even though he smelt like "rat p**s".
He quipped to Heat magazine: I like Hilary Swank, because she's sort of tough
The 'Love Today' singer's most memorable smooch took place nine years ago in a river in London when he was a drunk, lovelorn teenager.
He said: "It was near the river in Hammersmith. I was drunk and we were on the bank, and I stepped back into the water and got wet. I smelt like rat p**s, but it was a phenomenal snog."
The 26-year-old singer has always been vague about his sexuality, but admits he has a soft spot for "tough" actress Hilary Swank and hunky US singer Michael Buble.
He quipped to Heat magazine: "I like Hilary Swank, because she's sort of tough. Michael Buble kissed me at the Royal Variety Performance - not on the mouth, I wouldn't let him."
Mika recently admitted he is in a relationship, but refused confirm whether it is with a male or female.
He explained: "I'm private about my private life and I think that's an important thing. It's not necessarily retaining mystery , it's preserving yourself so you can sit down and write a song without feeling like you've sterilised yourself to be nice to everybody.
"I discuss my sexuality in my lyrics more than anybody in pop music. There's a way to discuss sexuality without labels. It's not born out of fear because you don't make music like mine if you're operating from a position of fear, that's for sure."