The chattering of the high schoolers could be heard from the corridors of the classroom as you walked to the last classroom at the end of the hallway. You stood at the doorway, waiting for your husband, Jiwoong, to wrap up his end-of-school tutorials for the day. "What's the formula for taking out the integrating agent?" you heard his sudden soft voice which pierced through the faint chattering of the few students present. The students showed him the answers on their notebooks as he wraps up the class finally, which woke you up from a trance with the few students rushing out of the classroom, not forgetting to bow down as a sign of respect towards you. After the students leave, you enter his class with a smile as you sit down on one of the empty benches. "Integration it is", he smiles a bit before wiping the whiteboard off. "Did you take up math in high school?" he asks curiously to which you shake your head. "It was either biology or math, I wouldn't give up biology for the world", you chuckle a bit as you look at the math worksheets. "Did you finish your surgery earlier? I thought it was going to be midnight until you would arrive", he ask as he leans on his desk, looking at you with love in his eyes.