So, this is just my opinion, my thoughts about Korea. Since i just came back from Korea few days back, i started to miss Korean already. This didn't happened to me when i came back from other countries that i'd been to but why Korea? Simple. It's because of these 4 things: People, places, food and things to shop in Korea.
For the people, why? Most of them are very helpful. Yes they might stare and look at you because you are a foreigner(they are just curious, it's normal) but when you need help, they will try their best to speak in English to give you the information that you need. Also, i'm actually impressed with people working in retail shops, restaurants and more. I went into shops in Korea. First, they greet you warmly, and after that when you went in to the shop, they try to assist you as warmly as possible.I'm really very very very happy to shop around in Seoul. And when i was in the subway or walking on the streets, there's people greeting me (i was shocked) and asked me where i come from and how's my views on Seoul. Don't be afraid to talk to them, they are really nice people trying to strike a conversation with a foreigner. Also, if you are going to Seoul, bring a korean phrasebook with you in case you might need it :D
Note: If you are in the subway, don't seat at the prioritize seats even when there's no people or you are deadly tired. Stand or sit at the seats available for the non-prioritize ones. (This is what i observed. I never saw any young ones/age 30-40 sitting at the reserved seats.
For the places, i went to beautiful places like their palaces, shopping districts (Edae, Myeongdong, Hongdae, Dongdaemun and more), cafes, hangang river, buildings (Blue house, national assembly, KBS, SBS and more). Since it's my first time in Seoul, i'm more interested to explore more and satisfy my fan-girl thing. But for the 10 days i'm in Seoul, i always always go to Edae (My favourite place): a lot of street foods, foods, cafes, cheap shopping stuff.
I didn't went to Everland but i went to Lotte world instead. Okay for me lotte world is boring. It's really not for me, because i went at night and the most of the games are indoors, i just feel bored. So i think Everland would be a better choice really even though it's a lil bit much more expensive. But you can go to Lotte world though, there's lotte mart there (supermarket) and more!
Also i went to a club under YG. I forgotten the club name but it was in Hongdae and the club is really..... the best club i've ever visit. So many handsome koreans and pretty koreans and.... yes just be careful and take care of yourself over there! If you have a friend there to accompany you to the club it would be much better!
For the Karaoke room, i can tell you that's the happiest moment in my life. Its very very cheap and there's all the kpop songs that i'm dying to sing it. So i get to sing all my korean songs and really, you have to go to the karaoke in Seoul. HAHA
Also, i realized every Koreans no matter where i go dressed up. The boys are wearing nice casual clothes while the ladies are all up with makeups and pretty clothing with their silky hair (ah i envy them)
For the food, my favorite food there would be definitely kimbab and their banana milk. OMG. I ate kimbab and banana milk every day + one meal (either kimchi stew, bbq or whatever) but i still lose weight! I'm not kidding! I did lose weight and i felt so small when i'm in Korea haha. Because my hotel is in Myeongdong so i have no problem in finding food and all.
For the ones that can't eat pork and is a muslim, there's limited halal food there however you can drop by Itaewon as there are shops selling kebabs and there's a beautiful mosque down there (i swear the mosque is really beautiful) and if you need more reference about halal foods in Korea, you can search over at the internet ya.
Whatever it is, I love Korea i love Seoul :D