Odo: Nerys – I realize that things may seem bleak at the moment; but there’s always hope.
Kira Nerys: When did you turn into an optimist?
Odo: Must have been that day in front of Quark’s when we kissed for the first time.
Kira Nerys: That was some kiss, wasn’t it?
Odo: Changed my life.
Star Trek: Deep Space Nine, Season 7: Episode 1 – “Image in the Sand”