The singer holds both the why and the I. It may or may not be part of the song but I think it also has a segment where the singer goes up a pitch?
Edit: the parts I remmeber sound like and it has a very laid back instrumental track, focusing the voice:
but Whyyyyyyyyyy
do you keEep coming back to meeee
and Iiiiiiiiiiiii
*unintelligible

I also found this one, that fits your description better: https://www.youtube.com/watch?v=kqA-4N72cuw&list=RDkqA-4N72cuw