MC, teen(?) has special powers (or is time traveller?). Ends up with his girlfriend and her mum (+others) as lovers. GF's brother is in the US forces (marine?). Brother discovers MC's secret, and when driving with MC to a secluded spot expects MC to kill him, but they only went there to talk. Possibly donations to Marine's charity.
Been driving me nuts for days now, and I have been hoping it would jump into my forebrain while gardening, but NO!
I know it's not much to go on, but just maybe??
