How do you report players outside of a game again?

Had a troll ban our ADCs pick intent (they were first pick) and then queue as cass jungle. Their name was a very vulgar term, too. Like I don't care obviously but kids do play this game. I dodged to save my team from that horror but took a screenshot and would still like to report the player. I thought you were supposed to open a ticket, but there aren't any options for something like this