im going to agree with ausbit; you quite literally said: "here i give you monies" (lol) and sent bitcoin to his address. no discussion of loan agreements, just you acting rashly. if op decides not to pay it back its entirely your fault as you gave away money. do you think banks or loan sharks just say "hey man heres some money go have fun now?" they get an agreement on repayment, interest rates, etc, none of which you bothered to even consider.