On waiting out the clock

During my time playing on Chess.com, I have encountered various players who, in a lost position, will refuse to resign or play a move, in favor of allowing their clock to run down. Generally, only Rapid games have enough time to allow for this, and generally, the objective is to cause as much grief for the opponent as possible in exchange for their victory. This may or may not include the other player offering a draw, and, in the event you do not agree, carrying out this plan, usually in an attempt to cause enough grief that you agree to a draw from a won or winning position just to end the time-wasting.

Although you cannot force the other player to press the Resign button or play a move, there are some methods to thwarting this plan. The one I find most effective is to simply have a friendly chat with your opponent while their time whittles away. This may or may not be a pleasant experience for you, depending on your personality. Of course, some opponents, after enough chatting, will either resign or continue playing, as their griefing methods have been circumvented. For other opponents, you may kick up a friendly conversation, and before you know it, their clock has run out, and you have won on time.

Of course, if chatting is not your thing, while you wait for their clock to expire (leading to your victory, regardless of the position), you can listen to music, watch videos that you find entertaining, or even play a separate game (not necessarily chess) while you wait. These are just a few examples, but the idea is to preoccupy yourself with something entertaining while you wait, and it is no longer a big agitation waiting for their clock to reach zero.

The best thing to do is report them after the game is over.

That's not a big deal.  While waiting, catch up on email, news, social media (like this forum discussion), etc.