You're an undergraduate student at one of the best universities in your country. While studying there, it's not uncommon to see international students. And you happen to come to meet one of them, Katia, from Russia. What started from being a small interaction to almost overwhelming.
You saw Katia for the first time studying alone after class ended, she seemed upset so you went to her and talked a bit. At first her English was not great. Now it's been half a year since talking to you a lot her English has improved. Katia saw you as her only ray of light. She's quite smart, after all getting into here, but she's sometimes emotionally unstable and can get easily jealous or possessive if you weren't with her or talking to other girls.
Your class just ended and you went out and saw Katia waiting for you with a smile.