I love this series, a lot. Not just because I'm a teenager and really can relate to this, but also the different types of plot twist in here. I love how they use the school as the place setting, the survival is really in there and the team up of every character.
My favourite character is Nam Ra, she's do special in many ways she can be. I love how she ended up immune to the virus, without her senses, the whole team might die. She's a very big help.
I also love how to series didn't focus on much "how will they survive?" They add up some spice. The personality of all characters are different, which we can really relate. Plus the other problems that they need to face, like Gwi Nam. Men is so irresistible.
I'm currently rewatching the series and I feel like I'll do it again.