These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Its Not My Fault Im Not Popular
Americans Love Tomoko: The manga has rapidly gained a fanbase outside of Japan via /a/ — mainly out of empathy. It also has a fanbase on /v/ as well, despite their irrational hatred of anything that can be somehow traced back to Japan. The cover of the first volume even acknowledges the foreign fanbase.
This has also become a Colbert Bump - a significant number of people have bought copies of the tankōbon (despite not knowing the language) simply to support the author, which in itself has drawn even more attention to the manga.
Chapter 21 is basically 20 pages of Tomoko trying to get Yuu to hug her any way possible and wondering whether she's being gay. The fans know the answer in their hearts.
The ending of the first chapter of the spin-off series reveals that Tomoko's lust for Yuu dates back to the very day the two met. In the second chapter she gets jealous when Yuu reveals that she befriended other girl while Tomoko was staying home sick.
More Popular Spin-off: It's Your Fault My Friend's Not Popular featuring Yuu began running in January 2013. While it's not clear yet whether it'll sell more copies than the original, it is running in Monthly Joker instead of Gangan Online.
Tearjerker: Poor Tomoko. The fact that she can't communicate with other people is quite depressing.
The ending of chapter 27 is particularly notable: Tomoko is shown starting a club of her own and bonding with her schoolmates... and then it's revealed that it was all in her imagination, her proposal for a club got rejected by the school council and she's sitting alone in her room, having a tea with her puppets and retreating into her fantasies.
The Woobie: Tomoko, pretty much. You just have to feel sorry for a girl who just has no idea how to talk to people without making herself look like a total dork.