Are you sure it's not just because of his british accent ?

haha
In all seriousness, obviously try and enjoy the next week or two with him as much as possible but don't get too attached! I reckon there are certain personalities which just click straight away and if the circumstances are appropriate then they blossom to a special connection or instant connection etc.
However, you guys should re-evaluate your positions once he gets back to England because anything could pop up while he is over there and then make your decisions whether you want to take it further or not

. My tip is don't get too attached too quickly and enjoy the time you have right now

. I hope it works out well for you