Initially, he probably thought that he was
lucky - to be about hook up a young lady and end up making out with
her. Surely, both lust and emotional void were present, serving as
catalysis for this scenario to take flight. There are unresolved
needs and therefore actions will be taken to satisfy them under
Freudian theory, this is the ID component and in astrology, thats
govern by Mars.
Your befuddlement stemmed from your personal justification in your
case. Beyond those well-articulated words, you painted a phantasmal
outlook that has failed to take on substance and conjure a form
(a relationship). It remains as hollow as you first uncovered, akin
to a maw of blackness, constantly mutating and evolving from some
macabre shade of darkness. You tried to figure out the undulating
shape - gradually you realized it has no definite structure and
everything existed solely on how you deemed fit all areas and
perimeters are perpetually reframing.
Strangers? Both yes and no.
Causal Friends? Both yes and no.
Good friends? Both yes and no.
BGR? Both yes and no.
Sex buddy? Both yes and no.
And it doesnt matter how long this list were to be as either one
of you can conveniently make length, width or height adjustments to
fit the puzzle.
Then it comes to the part about 'something more than just bed
buddy'; the journey has come to a juncture where you had no other
alternatives but 'coerced to believe' that this must be something
more than just sexual, simply because he display acts of
'asking dates, holding your
hands, laughing a lot and simply being'.
Humans often justify their own existence on Earth by claiming that
they have a 'mission' during their short stay here. But what if the
truth is such that life is but a meaningless cycle to debunk
conventional ideology? You will probably encounter scores of people
upbraiding you that it's not like that because there MUST be a
reason for our existence. There must be.
As confused as yourself, he might even query himself on whether he
still see you as a sex-buddy or has he really fell in love. In
fact, my analogy in the above paragraph might just happen - both of
you felt that there must be something more to it as the situations
has turned out to be this way and there MUST be a reason. There
must be.
But is there anything more? Apparently, it may not be. 
Cheers