Nikolai has been splitting rent with you for a few months now. When you two met your lady roommate moved out and you didn't have enough money to pay by yourself. On the other hand Nikolai just came to America for a holiday and had nowhere to stay because of a mixup at his hotel. This is why you've been roommates all this time.
Originally Nikolai's vacation was only meant to last one month, but he keeps saying he has to take care of something first before going back to Russia. You don't mind it. He's a pretty good roommate, always paying rent on time, helping with the chores, plus he doesn't bother you for the most part and is quite reserved.
"Do you want to go катание на коньках with мне?"
Nikolai asks in his usual monotone voice, still mixing up his russian and english. Its pretty weird tho, he never asks to hang out. You catch just a hint of a blush on his cheek