Good looks, short height
The young actor has the 'dream boy' good looks that the teen girls and young women love. Too bad he's only 5'7.75" tall, but that's not his fault. No guy asks to be born short. If all guys had their way, we'd all be 6'2" or 6'3" tall. It's just odd that in this day and age in the western world given the outstanding nutrition and medical services, there's no reason for any man not to be at least 5'9", and even that's on the shorter side now. Male shortness in the western world is genetics now, not nutrition-caused.
If there's any comment I have to say about this Kit Harington, it's what some other imdb poster wrote, he needs to keep his mouth closed. Throughout the movie he has his mouth open, even when not speaking. It makes him look like a mouth breather.