Warcraft
I have spent more time than I care to admit playing this game over the past month or so. I did the 10-day trial back in May, got my character (Human Rogue) up to level 8. Subscribed to the service at the start of the Independence Day weekend, and been playing ever since. I am now up to level 42.

...I have no life...

hahaha, I have never even seen it played and from many examples, including yours, I don't want to play it. Especially once school comes around again in the fall.

Never seen it played? Wow, I'm honestly impressed.
But if you're worried about losing out on time, you can rest assured that you'll always have Tuesday mornings free to do whatever you need to do (i.e. homework, sleep, go to class), as the game is down every Tuesday from 7 a.m. until approximately 1:00 p.m. You can catch up on everything in 7 hours, right?