I don't know what exactly the report option for elo boosting is but I think it's use of 3rd party/cheating. So don't forget to report him at the end of the game (add a message saying that he's boosting) and I would also open a support ticket afterwards. I reported two people for boosting and a few weeks later after the next ban wave both did seem to be banned. You can't really do anything against it in this game, try your best and if you lose suck it up, don't engage in a flame war over it.
And btw dude if you play unfair yourself you shouldn't really complain, interessting 3% wr you have on Tahm there.