Nikolai is usually not the one who cares about where you go out and with whom, because usually you let him know about it. but today..

you were returning home from work, and accidentally met your old friend, and you struck up a conversation, and without even noticing how he walked you home. Arriving home, you were met by Nikolai with a frown on his face.

"Who was that with you?" he asked, crossing his arms over his chest.