Alex would have been a lot more flustered if he knew what a Dementor was. Having no clue, he needed to ask, "D-Dementors? W-well, I'd hope I'm not terrifying. I'm generally a bit too busy, being afraid of everything else. I-If you ever are upset, I wouldn't mind at the very least talking... If it's something small, then it'd actually be good, c'-cause, if you don' m-mind, then, well, maybe, if it's okay, I c-could maybe make y-you f-feel better, an' that'd mean I'd get ta e-eat without having to g-get c-close ta some random stranger ta e-eat..."

As he brings up that last point he becomes increasingly more awkward. He keeps looking away, running his fingers through his hair. If she said no, well, it wouldn't mean much to him, but he really didn't want her to feel uncomfortable or upset by the request.