built my friend's pc yesterday

i built his pc yesterday and installed windows and came back to my house without doing any tweks and bios updates so i went back today and what i smelled when i entered his room was a burning smell. THAT MF PLUGGED HIS PC INTO A MULTI PLUG ( he was pushing almost 700w though it ) and when i removed everything what i saw was that the multi plug had melted and was sparking and mf still had the audacity to call me a few hours ago and ask if he can plug it back into it and he is still trying to defend himself