Feeder always flame, blame and being toxic

SIgh....another day in League with a very toxic player. Being toxic is one thing but feeding too? Even his laner said this feeder is bad. Even the game ends, this toxic player will wanna act tough and trying to pick a real hand to hand fight with me by asking me to go to Massachusetts and see what happens. LOL? I admit when there are games i did badly, I kept quite and tried to stay a positive mind by grouping up with my team instead of feeding even more. While this toxic feeder just kept feeding and flaming entire game then try to threaten me with a real fight.