Is it normal to have these fantasies?

Okay, I'm an 18 year old girl and I am lonely. I've never had a boyfriend and don't have many friends in the real world, because I live in a rural area so I often feel isolated. I often shut myself out from the world and just indulge in these fantasy storylines in my head, often so intense I need to write them down afterwards. I have this story and these characters in my head.
The storyline mainly focuses around these two brothers, both Korean. One, a North Korean soldier, 21, who grew up with his mother and no one else till she was publicly executed when he was 8. Then he was thrown into a labour camp but later he escaped. About a year ago he fled North Korea because his friend smuggled South Korean movies across the border so he made his way across China and then got rehabilitated in Seoul, where he met his half-brother.
The other being a typical South Korean guy of 19, who grew up in a rich christian household, and is also smart, musical, popular and good-looking, but also quite reserved and introverted in actuality. Well, they often fight and argue with each other over different things, and I involve myself in the storylines too, and sometimes it's about their past, or their life with me now.
I make comics of them and sometimes even hentai.. I even wrote erotic stories of them, often the plots are so elaborate and detailed. I feel like I am getting to know the characters in real life and I love exploring their different personalities and their very different upbringings. Sometimes, I feel like I'm falling in love with them... So, is this normal?