Thanks for taking time to review. Flash fiction, as you know, is more about what is implied rather than described/said. In my mind, I saw Sabir as a teenager frightened half to death by the tension-riddled environment in which he finds himself. So scared in fact of being badly beaten up that his ultimate reaction is completely out of character.
I liked most of this story. I like your style of writing, although some descriptive phrases ("Frankie's eyes open wide as if they've been pushed from the inside.") work better than others ("A giant jumping bean unzips my skn and climbs in.")
I liked your dialogue too. Although there is not much to differentiate McDonald and O'Brien (which is understandable given the short amount of dialogue) I think it was well written - I could really hear a Northern Irish accent in my head as I read the words.
I didn't like the line "A fifteen year old terrorist-in-waiting, or so they believe." I think it's a bit cliched and unnecessary, particularly given that to my knowledge Northern Ireland has never had a terrorist attack my muslims, but plenty by 'christians'.
The other bit I didn't like was the ending. It was certainly unexpected, and 'm a big fan of twists at the end of a short story. But nothing about the character I have learned up to that point convinces me that it's something he would do. It seems out of character. It's a shame as I really liked the story up to that point.