Is it normal my girlfriends first boyfriend at the age of 15 was a 34 year man?

Girls do like older guys, do you happen to be from Slovenia ? Just curious, my ex class mate was 15 when her first boyfriend was 34, don't know if the are still dating. It's a little weird but hey, what isn't weird in this god forsaken world ? Don't worry about it, she probably just wanted someone older and more mature, which happened to be a 34 old guy. Don't judge her.

At that age girls are vastly more mature than their male counterparts and often seek comfort of older males/females.

Given typical physical development at that age it is understandable that a 34 year old man would find her attractive. There is a large psychosocial gap between the two ages and it is unlikely to have been very fulfilling to either of them.

Normal? Hard to define normality in today's world.
Acceptable? Most likely not.
Understandable/comprehensible? Yes.

Obviously it's illegal (most places) but that doesn't mean it don't happen. It's probably more common than most people would think.

Not common, but in some countries it's legal. I have had a GF with that age difference but she was 22 at the time.

Indeed it IS normal for a girl to want a father figure
Guys just look for an easy encounter.
To what extent is/were the relationship?
Mainly physical, or were there a "real" connection ?

It's normal in some areas of the world.