Bring me the Moon: put both the people on the seagul, and wait til the moon is small,then give it to the guy.
No reason to live:put the guy on the seagul
Be free:put the girl on the seagul
Tragedy: kill either the guy or the girl.
I am your moon: put the guy on the boat and the girl on the moon
If i cant have you....: put both the guy and the girl on the boat.
Such a pretty sky: put 4 comets in the sky
Lost love: put the guy on the boat.
And that's how you get all the endings.