I had something similar happen to me. Someone picked Urgot, a champion I like and can play fairly well. I figured 'Oh, cool. Someone else likes Urgod! This could be a lot of fun! I wonder if our Qs can go to an ally's E DoT.' All throughout champion select, the guy that picked Urgot is talking with a teammate, and it's obvious they know each other IRL. The friend picks Urgot too, making it the manority, and we go into the game. We're against Heimerdinger, but I feel pretty confident.
The guy that first picked Urgot sits in base, seemingly AFK. I asked his friend if he was coming back and get an "idk". A few minutes in, he comes back and says "lol the plan was to pick urgot and afk". Just after this he DCs, then comes back.
Him: "wtf okay the game just kicked me"
Teammate: "It does that if you don't move for a while."
Him: "wtf thats stupid"
He comes to lane now, but is still constantly talking to his friend in chat. I was solo-top so he goes with me. They're both gossiping about people they work with, more than actually playing, so things aren't going well. At one point, he dives deep into two Heimers, getting one low before dying. I hang back, shooting Qs for as long as I can, nearly dying myself, but the Heimer escapes. Immediately, my 'ally' begins calling me racial slurs and other obscenities. The insults and stupid gossip continue all game long, and we surrender not long after the 20 minute mark. In post game chat, I asked for the guy to be reported, and his response was "lol racist? u must be a <slur>".
Got to love this community sometimes. -_-