South Park Season 9 I believe Episode 16 IIRC explains it in great detail and makes fun of it.
Who the hell actually belives aliens did all that?
Kimi wa ne tashika ni ano toki watashi no soba ni ita
Itsudatte itsudatte itsudatte
Sugu yoko de waratteita
Nakushitemo torimodosu kimi wo
I will never leave you