I had several encounters with high school guys or friends or friends in my small town.
Some have been understanding and are discreet.. Others have tried blackmailing me.
Reasons why he may be doing this wierd behaviour
1) he thinks you will tell someone, paranoid you will tell his gf, fam, etc.
2) doing it on purpose, thinking u give in eventually and give him freebies because your old "friends"
Either way ignoire him and block him. But this could also make it worse, what ever u do, it be 60% chance at least h(from what i gather from his behavour) that he contact your friends, fam,spread rumours.
Doesnt sound nice but be prepared!.
If he wants to get like that, always have the option of playing him at his own game, like finding something to blackmail him with like a embrassing fetish.
When i was blackmailed, i had pics of the guy cross dressing & images of him with other men.. He was too concerned about his image! So i was lucky lol
What ever you do , up to you hun
Good luck xx