MInecraft Server, and payment argument?

Hi, I payed my friend €10 so he could keep the server up for longer, he spent the money on sweets and it has yet to be used on the server as we're in the first month of payments and he has already payed for that with his own money. I had a fairly big dispute with him and his friends due to bullying of sorts and I want my money back.(€10). It's not a big claim but am I in the right to a refund of sorts, and if so is there any way i could sort of 'scare' or force him into paying me back, i can't do anything physical obviously, so can you help on this one?