After watching this drama, I can safely say that I'm an official sucker for friends-falling-in-love dramas. Firstly it happened to me while watching Reply 1997 and In Time With You, and now 9 End 2 outs. This drama is super sweet and super cute and soo funny! 30 years old best friends become room-mates and eventually realize how perfect they are for each other. The story is not that new. But yet it's great. The relationship between the two main characters would leave you envious. They're just so sweet to each other and so caring and they don't even realize it. Another plus point is that this story has a touch of realism. You can see how while living together these two people start behaving like a old married couple and how they learn new things about each other (one of them even making a list about it!) and both of them end up wondering "Why the hell am I not with this man/woman already? What have I been doing all my life??" lol. The cast and acting is great. This drama has various characters and all of them are awesome. Jung Joo is so funny and cute! The bickering between him and Hyung Tae were so entertaining XD And Yoona's debut as an actor (only learned that an hour ago). She was pretty good even though her role was semi-bitchy. I loved all the friends of Hyung Tae and Nan Hee. The chemistry between the two main leads is really really good. I'm really going to watch again sometime because I loved how they were with each other. They had this perfect balance of love and friendship. The music was great! I'm going to download the OST now :)