Just got yelled at for taking someone's role...even though I was given it by the champion select.

Got first pick for jungle in champion select. Guy asks if he could jungle and I take top, I say no. After I pick a champion, he brings up that he can't play top so I offer to just go Sejuani top so that he can jungle....and he refuses. Throughout the whole game he's complaining in both regular and all chat that I "took jg from him" trying to get people against me. Game ends, my team won with me and the top playing really well and carrying most of it and in end game chat he still tries to bring up that I "stole his role". Again...I was given jungle from the champion select because I queued for it.

I don't get some people @_@